Similes add color and tone to your writing. Don’t overdo. And avoid the worn and weary ones–such as hard as a rock, soft as a cotton ball, etc.
Make a list of fifty adjectives. They can be as simple as big, ugly, or shy. List the adjectives in a column, one adjective per line.
Turn each word into a simile by adding “as” and finishing the comparison. For example, ugly as a rotting stump. Try for comparisons that are fresh but meaningful.