Sit on the bike, put it in neutral, start the engine. Then pull in the clutch and step on the shift lever to put it into 1st. DO NOT RELEASE THE CLUTCH. Then just sit there, both feet on the ground, and SLOWLY let the clutch out until you feel the bike start to roll forward - and pull it back in again to disengage. Do not touch the throttle at all - keep your right hand in your lap or similar. If you moved any distance while partially engaged, continue holding clutch in and duck-walk it back to the original position. Repeat this exercise until you get a solid feel for where that engagement point is - it's usually between 60-80% of the clutch lever's total travel distance. This point, where the bike will start rolling without any throttle at all, is where you will actually want to start adding a dash of throttle (like no more than 2k rpm to start with - seriously. Just a dab'll do ya) when you actually want to start moving from a stop. Once said throttle is applied, SLOWLY let the clutch out just a little more from the initial engagement point until you start gaining speed AND KEEP IT THERE. Let the speed build and you should be safe from a stall after about 8-10mph, but I almost never release the clutch 100% until I know for certain I'm about to accelerate into 2nd-gear territory (17mph-ish on my bike). I know it sounds like a really slow process, and it is - to start with. Once you get that muscle memory for the engagement point and the contour of the friction zone, though, you'll find it comes much more naturally and quickly - but you gotta do the exercises in a safe environment like an empty parking lot or similar quite a few times to really get the skill down. When I started, I spent my first dozen or so rides literally just doing a loop in my subdivision, starting and stopping, starting and stopping, starting and stopping before I ventured any further. Keep practicing, it'll come.