How to turn a hand-drawn sketch into a digital illustration in Affinity Designer

In this tutorial, Matt shows you how to transform a hand-drawn sketch into a digital illustration for screen printing in Affinity Designer.

Watch Matt’s creative session, then read his written guide below.

Sketched idea to t-shirt mock-up in Affinity Designer with Matt Searston

Step 1: Initial sketch

Here’s the initial design I created for the session, first by making a pencil sketch and then by using some tracing paper to create a duplicated fine-line version. I wanted to keep this separate from my initial sketch as it’s always great to have the original drawing to refer back to and also to avoid any nightmare situations where your only copy becomes damaged and you’re back to square one.

I wanted the design to have a handmade feel, which is why I decided to go down the tracing paper and felt tip route. Alternatively, another option (which I often opt for) is to sketch directly in Affinity Designer using either the Pencil Tool [N] or the Brush Tool [B].

Step 2: Create a new document in Designer

In this tutorial, we’re planning to create something that can be screen printed onto t-shirts and posters, so I would say creating an A3 Portrait document in CMYK and at 300 DPI would be the best way to start. This way you avoid getting to the end of the design process only to realise your design isn’t large enough for the intended purpose. It also gives you more options to adapt the design in the future.

If you’ve opted to draw your sketch digitally, you can go ahead and skip to Step 6: Adding colour to your design.

Step 3: Place your sketch

Assuming you’re using the same method as me and you’re going for a slightly more handmade look, we now need to get our inked drawing into the Designer document so we can start to digitise it.

Ideally, you would use a scanner to get a nice high-resolution scan of your drawing but I usually just use my phone camera with a good amount of daylight around. This is really important as the next step is much easier to do if we have a clear, bright image to work with.

Once you have an image of your sketch, go to File > Place then locate and open the file and click on your document to place it.

Step 4: Adjustment layers

Now we have our inked image in place we need to make sure it is as highly contrasting as possible. The best way to do this is by adding a Brightness/Contrast Adjustment.

We can do this by selecting our layer on the Layers Panel, and by going to Layer > New Adjustment > Brightness/Contrast or by clicking on the Adjustments icon within the Layers Panel too.

Now we have the dialog open we can tweak the settings to create more contrast in the image. What we want to end up with is a very clear separation between our drawn ink lines and the blank parts of our paper.

Step 5: Using the Flood Fill Tool

Now it starts to get a bit more fun. Firstly, we need to head over to the top left corner of our screen and switch to the Pixel Persona. This enables us to use a different set of tools to digitise our image.

Now we’re in the Pixel Persona we need to create a new Pixel Layer by going to Layer > New Pixel Layer or by clicking on the little chequered icon at the bottom of our Layer Panel (ensuring that the new layer is placed above our inked drawing layer), then we need to grab the Flood Fill Tool [G] from the Tools Panel to the left-hand side of our document.

In the Context Toolbar at the top of the screen, we need to make sure we change the Source to Layers Beneath. Otherwise when we go to fill our chosen area, it will automatically fill the whole of the pixel layer itself, whereas, with Layers Beneath selected, it will only apply the fill to the pixel data in the layers underneath our current one.

We also need to ensure that we have our threshold set to somewhere between 20-60%, but the actual amount is up to you. A higher percentage will allow more of your image to be filled and a lower percentage will fill a smaller amount, so I usually find around 40% is the sweet spot, but it might be worth trying a couple of different settings to ensure you get the best results.

Finally, Contiguous needs to be turned off, as in this case, we want to fill the whole inked drawing with one single click without having to individually fill each line, so this is a really important setting to change.

Now, all we need to do is chose our fill colour from the Colour Panel (I’m using black for this example as it will come in handy further down the line), zoom into our drawing and simply click on the inked area to instantly create a duplicated version of our design, this time without any background whatsoever. This will give us complete freedom in the next steps of our design and (more importantly) more flexibility for printing or other purposes in the future!

Step 6: Adding colour

Now let’s start to add some colour to our design. For this step, I feel it’s really important to make a new Pixel Layer each time we want to change the colour. We could also break down these new pixel layers into different sections of our design to give ourselves even more flexibility.

As I wanted to create something really bright and eye-catching I decided to use bold colours during this next step. By using the Flood Fill Tool [G] again, you can simply go through the design and fill it with blocks of colour.

This time we want to turn the Contiguous option on as we now want to be more precise and spend a bit more time considering where these filled areas need to go. Now we’re filling in with the Flood Fill Tool we need to make sure we click in the empty spaces instead of clicking on the previously inked line areas we did before.

Step 7: Adding other elements

I wanted to create a retro feel to my image, so I decided to put the brand name around my design in a surrounding circle. This is easily achieved firstly by creating a circular path using the Ellipse Tool (make sure you’re in the Designer Persona during these next steps). Then once that is in place select the Artistic Text Tool, click on the path of the ellipse and begin typing.

This is a great way to add some extra dynamics to your design and gives you a great chance to show off the name of the brand at the same time as combining it with an eye-catching illustration. This works perfectly when creating a design intended for merchandise like a t-shirt or tote-style bag.

Step 8: Putting our design in situ

This last step is really simple and quick to put together. For my t-shirt mock-up, I’ve just used a basic blank t-shirt template image. These are readily available from many stock websites, but for this example, I used an image from Shutterstock which had the ideal layout I was looking for.

Now what we want to do is drag or place our t-shirt image into our document (ideally onto a separate artboard as this will make life easier when we come to export our imagery) and bring our illustrated design on top of the mock-up image.

One quick and easy way you can do this is to group together the line areas of your design, along with your separated coloured layers by selecting them on the Layers Panel and going to Layer > Group and then making a duplication of this new group, which you can use to place over the top of your t-shirt mock-up.

Now the design is in place we just need to go over to the layer blend mode and experiment with some of the options we have there. I found that Multiply is the best option in this case, but see which works best for you. With a bit of experimentation you’ll be able to see some of the texture from the t-shirt blend come through to your design and ultimately end up with a realistic-looking t-shirt mock-up!

Step 9: Final tweaks and preparing for print

All that’s left to do now is export our image for printing and to use online too. The print method you decide to go with will largely impact what kind of file you’ll need to create.

For example, the traditional screen printing method I mentioned earlier requires multiple files to be exported to replicate the various colours in a design (the individual requirements are often fairly specific to the printer you are working with so you’ll need to confirm with your screen printing company of choice, exactly how they will require your design to be sent).

Direct to Garment Printing (DTG) is however another option you can use, which requires less file preparation to be print ready. The most common route when using this option is to export a high-resolution PNG or TIFF file, with a transparent background also enabled within the image. Thankfully, due to the way we’ve created our design by separating our linework from our initial background paper layer, we simply need to go to Document > Document Setup at the top of the screen, select the colour settings and check the Transparent Background tick box.

This means that you can easily print onto garments and other items without having to have a white border around your image and it allows you to seamlessly blend your designs into the background of what you’re printing onto!

Hopefully, you’ve found some useful techniques and workflow examples to inspire you in this tutorial. You’ll also find a previous creative session on YouTube where I selected a stock image as my base reference and then used the Pencil Tool and drawing stabilisers to draw an image so feel free to check that video out too for further inspiration.