There is a simple way to add colour to watercolour brushes - just pick a colour and draw. This method is fast and easy, but inefficient if you'd like to colour png shapes, or if you'd like to be able to change colours later on.
In this tutorial I dabbled in some of the non-destructive colouring techniques. I hope they'll help you make the most of your watercolour brushes. Have fun learning!
Step 1: Pick a grey colour and draw your shapes
Choose a shade of grey (mine is #777777) and draw your design. If you are using a transparent png graphic, make sure you have it on a separate layer.
Step 2: Change blending mode of layers and add colour
Create a new layer (Colour Layer) on top of the Shape Layer and set its Blending Mode to Overlay. Go to the Layer menu and Create Clipping Mask.You can also try Soft Light or Hard Light and see what works best for you. Your file is ready - just choose a soft brush and a colour and draw on the Colour Layer.
This is it really. As you can see there is a small change between the two shapes. You can either leave it like this or add some details (just keep reading :) ).
Add colours and depth
One of the best things when using this non-destructive colouring method is that you can change your mind as many times you want. To blend colours or create gradients, add new colours with a soft brush (just make sure you are painting on the Colour Layer).
To add depth create a Second Colour Layer and set its Blending Mode to Overlay. Pick a smaller brush and add details to your shape.
Colouring small details
Another cool thing of this technique is that there is a very easy way to paint details in different colours. Pick a small hard brush and go carefully over the parts of the grey shape you would like paint in the selected colour.
That's it! Thanks for reading and spread the word if you liked the tutorial
I developed these techniques while experimenting with watercolour brushes and struggling with the editing. If you have a better way оf colouring shapes in Photoshop, please share it in the comments below - I'll be happy to try it!