Watercolor artists have varying opinions on how to produce white with watercolor. But perhaps "produce white" is misleading because actually, what most artist do is to preserve the white of the paper to achieve white in their work.

Most artist are from the school of thought that it's best to keep the white of the paper free from color while other artist will use mediums, like white ink or acrylic paint to incorporate white in their work. 

I’m from the school of thought that you should do whatever works. After all, here are no watercolor laws that will be broken or watercolor police that will cite you if you use one method over the other. 

3 Methods Outlined

1. Freehand/Paint Around

2. Resist

3. Paint/ Write Over

Freehand

The freehand method requires a steady hand and some preparation.  In my example below, I lightly traced out the design and after the watercolor completely dried, I went back and erased. If you use pencil, be careful not to paint over the pencil as it cannot be erased once painted over.  

Resist

The resist method uses things to act as a barrier between the paper and watercolor. Some mediums or barriers work better than others.  Below are examples of masking fluids, stickers, and wax. 

Paint Over

Another way to incorporate white is to write over the watercolor with ink or paint over it with acrylic paint. 

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