How do you all get clean lines? (Beginner here)

New to painting and even newer to gouache, but what I have loved about exploring this medium is the creaminess & blendability compared to acrylic. I have a love/hate (but mostly love) with how it’s able to reactivate.

Blending has been so satisfying but I am really struggling with definition when I want it. It’s hard to not end up muddying.

Things I’ve come to be aware of to keep in mind:

• letting layers dry before adding another

• controlling the water usage, using less as you layer on

I’ve been using watercolor brushes but I’m wondering, should I use acrylic brushes for top layers instead? Or could it be the watercolor paper I’m practicing on doesn’t have enough weight?

Would love any insight especially from anyone who has had a similar issue in the past.

Love seeing all the wonderful inspo + progress work in this sub btw. TIA!