It may have a little to do with the
vaping, actually. PG and VG cause dryness. Combined with the heat (I have problems with it, too!), no wonder you are getting nose bleeds.
1)Drink plenty of fluids to prevent the nosebleeds.
2)When you get a nosebleed, dampen a washcloth with cold water and pinch your nostrils with it. You may tilt your head back -- I always do, but I've heard those that say don't. Hold it for at least a couple of minutes and then check. Avoid the temptation to blow your nose right away -- this could dislodge the clot.