Hi Kathleen, don’t worry when you begin it a learning curve for everyone, to stop muddy colours just drop the colour in to the area you are working on and don’t move your brush on the paper to much, this is what causes muddy colours, and also leave a little gap between the areas you r are painting then just tap them together this will retain the colours in these 2 or 3 areas before your let them merge…hope this helps Take care Andrew