Ever wonder why that Water Bottle is in the net in EPL or MLS games? Its not just for a thirsty keeper! In order to have the best grip with most Latex's - especially Giga Grip, you must keep the palms damp. Spit works ok, but on very dry days, you need water on your gloves before you start training or warming up and every 15-30 minutes after. (The reverse is true on a wet day, just grab a dry towel and SQUEEZE the moisture out).
The water activates the chemical treatments that the gloves have undergone, opening up the pores- making it far more tacky and sticky. It will also make the gloves last substantially longer- a dry glove will wear away much faster and start to chip apart!
You don't have to soak your hands but a good squirt of water will get the grips activated - as the weather gets nicer, keep the water close for hydration and give the gloves a squirt as you take a drink on a warm day with Giga Grip Latex, you will be surprised how much of a difference it makes!