The easiest and most effective thing you can do to prolong the life of your hockey stick blades is to tape and wax them very well. Since you naturally lose grip on the puck if your blades are wet, taping the blade of your stick prevents moisture from building up on the blade and keeps the puck from sliding off.
Decide whether you prefer to tape from toe-to-heel (more resistance) or heel-to-toe (less resistance). There's no right or wrong way. Wind the tape around the blade, overlapping layers by about half the width of the tape as you go.
Once your hockey stick blade has been taped, take a puck and rub it along the tape area, in the heel to toe direction. This will create a smooth surface for the newly attached tape and will also bind it well with the blade. Apply a thin layer of the stick wax to the blade area which you have just taped and the bottom of the blade (the part that comes in contact with the ice). The layer of wax makes the bottom of the blade slick and also provides a watertight layer of protection to keep the tape from unraveling due to moisture. Wax increases the life of the tape by preventing water from settling on the tape. It also helps while you take shots, by reducing friction between the ice and your stick blade while striking the puck.