get some paper and a pen and start drawing simple stuff or redrawing random manga panels as close as possible, then after a while you'll start getting some drawing ideas on your own. after a while tho, you'll probs need some kind of drawing pad/tablet if you want to "upgrade" to the lext level.
it's important to have fun drawing. this will fuel your drive to continue on.
draw the things you like but don't bite off more than you can chew. start with simple stuff if you have difficulty to do it then do something more simple. ; )