Two Similarities Between Painting and Writing
#1: Learning technique: the first step.
For both medias, writing and painting, learning the core concepts will give your creative whim credibility.
In writing understanding sentence structure is will get you winning words, be it punctuation, participles, or prepositions. Personally I struggle with all of them.
In art, structure is vital. Mastering the basic technique of transcribing details and learning the vanishing point of perspective is the underlying strength to painting.
Once you understand the essentials, you'll see your work grow when ...
#2: You allow your creativity to flow. This is the joy that makes all the practice worth the effort. In writing, as much as I enjoy wildly putting my thoughts on paper, I've learned it is best to let the musing rest overnight and critique it the next day. Re-writing is an essential step for me.
With painting I tend to be a non-sketcher so it often takes re-doing pieces to get the end results I desire. Like in writing, erasers work in painting, too. To illustrate, below is a watercolor I have lightened the colors on the right side which prepares the paper for re-painting allowing for a second chance to capture the beauty of the flowers.
I image cooking, dancing, and other arts involve the same two step process. Have you discovered that in your own creative endeavors?