I've just lumed a set of hands, so I paid attention to what I was doing. I always use a wooden toothpick/cocktail stick to lume hands, as you need a fair amount of lume on the end to cover the Mercedes hour hand.
Lume mix should hold a rounded dome, and when you pull the toothpick out of the mix it should leave a peak which drops back down - it should not be instantaneous, it should take 1/2 a second or so to drop back to a smooth, rounded dome.
The hands are under side up, I put a ball of lume on the end of the toothpick - it's not smeared up the length of it. I make contact with the base of the hand, before the apertures, with the ball of lume, then pull it up over the rest of the hand.
I used to have problems with lume dropping down through the apertures and thought it was gravity, but I think the weight of the lume wouldn't be enough for this to happen - add in surface tension and viscosity and it's even more unlikely. I found the reason my lume dropped down into the aperture was mix to thin, applying too much mix, and probably the biggest reason, having the lume applicator coming too close to the hands and pushing the mix down into the apertures - shaking hands (or hands that shake) will do the same thing.
The toothpick is just used to pull the mixture over the surface of the hands, it doesn't touch the hands - surface tension and viscosity are what keeps the mix on both the applicator and the hands.