Just remember to always use a main plot and not to branch it off to much or you will end up like hit man reborn... Cancelled
when I write a plot I usually draw the manga boxes ( where you would usually see the faces and images) and write the plot in them. It just helps me write a better story and because you said you can't draw it kinda impowers you to say you are usin the part of the manga where the pictures are drawn for the plot.
also post or pm when you are finished because I want to here your story
Gintama Is Back
Please visit my new anime and manga blog( I want to make it GOOD)