Hi. this is Pays164, and this is how to control your spray paint can, and how to use your graffiti caps. Very simply, grasp your spray paint can. Get a good grip just with enough room to slide your finger right on the top. You don't want to get it too high, and end up getting too much fatigue in your knuckle, just from trying to lean and press down on it. Just relax, grab it, and rock and roll.
Using these spray paint tips, first and foremost, don't just ram them on the top. You're going to end up bending the nipple of the can, or chipping the tip, and not being able to use it at all. Simply take the tip, twist it in place, and you're ready to go. The same with removing the tip; when you're getting it off, you twist it back off. Every time you do this, you allow it to not damage the nipple of the can, and the tip of the spray paint tip. Again, lay it on. Twist it in place. Twist it off. That's all it took. It ensures the life of your tips as you switch out to different types to get different sizes and different techniques.