I am getting better at creating motives now and record them, but when I want to write them down, I have trouble putting the rythm down accurately, any tips?
It is useful to separate out the task of transcribing rhythm from transcribing the pitches. First, determine the beat and meter. Is it 4/4, 6/8, 12/8, etc? Once you’ve determined that, then attempt to sing the rhythm out loud without worrying about pitch, keep it at one single pitch, and use a syllable like “ba”.
Pay attention to notes that fall on the beats, and those that fall before or after beats. Work your way through the basic idea, one note at a time. You will probably end up singing through the rhythm many times before you finally get it down.
A good way to practice this is transcribing music that others have written, straight from recordings. This allows you to practice and then check it against the score, to see if you got it correct. Feedback is helpful when learning to transcribe.