As professional illustrator I find sketching some objets and textures terrible boring and time wasting. Things as wooden boards, shelfs with books, trees in a forest, infinite number of flowers or windows in a city skyline, etc... can take really a lot of time! Here is when I can help you. I have create a variety of elements that always are repeating in illustrations so you don't have to draw it one by one. Save time in your sketches so you can spend it in what really matters. Works for Photoshop and Procreate. (Please follow the tutorial if you don't know how to use it).