I've been using hairspray to install my grips, and have for 20+ years without fail...as long as I steer clear of the fancy "soft hold" crap. You need the kind that makes your hair feel crispy like you sprayed it with a coat of polyurethane. Buy the smallest, cheapest can of aerosol hairspray you can find (trial size is great) and it'll last for years. Somewhere around here I still have a can of Aqua-Net that I bought in the late 90's.

Grip glue works great, too...but it's more expensive and doesn't last as long in my toolbox.