How can i keep my foils from slipping,i always get spots!?

whenever i do foils they always slip and leave spots.i hate it sooooo much.any tips or techniques for keepin them suckers in their place?How can i keep my foils from slipping,i always get spots!?
spots make sure you have full coverage in that foil start off the scalp not on the scalp. foils if pinched and using hair foil shouldn't slip, try using papers from Sally's beauty supply that are just like foils but are a adherent paper. there called highlighters paper. How can i keep my foils from slipping,i always get spots!?
Well, it's a bit hard to put into words but you need to remember to back that s%$t up! If you're using a decolorizer, make your consistency a bit dryer and allow for swelling. I prefer to use a very thin foil and the way I fold it allows me to bump it up easily. When using a high lift you really have to back it up ( the loose consistency of tints really is conducive to bleeding!) and be very gentle when bumping it so as not to ';squish'; the product out of the foils. Check it often if you put it under the dryer. I pin up the foils and work from top to bottom (Front to back for tints, back to front for decolorizers) so that they're out of my way when I apply the next foil and I can get a taut tension directly against the head (If I went bottom to top, I would run the risk of squishing the foil underneath the one I'm currently adding.) ALWAYS inform you clients not to smash the foils while under the dryer!!! THe nape of the neck and crown of the head are ripe for bleeders, be especially careful in these areas!