And make sure you read up, if you haven't already done so, on how to climb and descend your ladder.
I've seen loads of guys climb/descend ladders with their hands on the uprights and NOT on the rungs..... if your foot slips off a rung and you haven't got your hand on a rung you are going to hit the ground. You just can't save yourself by holding on to the uprights. Sounds silly but it's worth having a few practice goes. Some people will advise you to only move one limb at a time.
None slip footwear is a must too.
As a previous poster said, it's better to get a wider ladder with D rungs. I don't think long wooden ladders have D rungs, but I could be wrong. They are much heavier too.
My own dad, when he was alive, slipped off his wooden ladder (no D rungs) and cracked a number of ribs.