Types of prewriting include: drawing, freewriting, brainstorming/listing, clustering/mapping, Asking Questions, Outlining.
Drawing is more for visual learners where you literally draw out what information you want to use and where.
Free-writing is kind of like a draft, where you just write what you're thinking and then come back to it once you've finished to edit and perfect it.
Brainstorming/ listing is just like it sounds and like you've done for before writing since kindergarten. You list ideas and thoughts of what you could include in your writing and go through it to group things that can go in the same paragraph and get rid of things that stand alone or aren't the best pieces of information.
Clustering or mapping is similar to brainstorming but this is where you use the information gathered from the brainstorming and map out where in your writing you want to use those groups you made.
Asking questions is just what it sounds like. This is where you can confirm information you have and get opinions on your writing.
Outlining is where you start to put the groups from brainstorming and clustering into your paragraphs. You make a quick outline of what information you want in which paragraph. You can add or erase paragraphs, you can do whatever you need to in the outlining. It really helps to make sure the writing flows nicely.