ok so i know how to compose decent songs with guitar bass and other instruments and ive studied music theory but is there a way that you go about learning what part of a drum set goes with what or how to mix them up and stuff like theres scales and chords for usual instruments like is there a such thing as percussion theory? i know theres toms and crash and cymbals n stuff but how do you learn what sounds good with what n such and how do you go about creating different fills n stuff
No. The purpose of the drums is just rhythm usually. Use the snare and cymbals to accent beats you want to stand out. Kick drum usually follows with the bass.

I don't think you can really tell someone how to "write" drum parts to be honest. Unless you're talking about timpani and other chromatic percussions but I think you talking about regular drum kits.

I guess a general rule is you want the drums to match the beat of the song.....yeah a drummer better handle this one.....
If you listen to the "one-man-projects" on youtube, where one person has written all the parts to a song you can usually if not always tell when that person is a drummer or not, by the drum parts.
It doesn't necessarily come from complexity or even learning theory, it's just being able to hear what sounds good in a certain part. It's too easy just to either stick a four to the floor rhythm behind everything, or put in a well known rhythm that's catchy. Just write a riff, record it, listen to it on a loop over and over, and air drum to it until you get a good enough feel what the groove should be (where the accents are) then just play around until you get something you're happy with.
this probably isn't correct so to speak but I just write drum parts that I think sound good with the song. I use guitar pro, write a riff and then write a drum part that sounds good underneath it. If it sounds good I'll use it, if not I'll scrap it and come up with something that does.

I know nothing about drums, so my stuff will probably offend an actual drummer's sensibilities. Its music man, just write something that sounds good. As far as the actual sheet music for deums I let guitarpro handle that, I just select the type of note I want (16th, 8th, quarter, etc) and click the window that brings up the drum list and just click the one I want. Copy and paste the verses and choruses and whatnot making sure to change up the fills and small details like hihats so it sounds more realistic.
wow, words fail me guys.

Get "rhythm section drumming" by frank corniola
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