That's far and away the most important thing. Read profusely - books, magazines, specialist tomes - and try to work out what interests you before you jump too quick.
A good starting point would be Collectors Coins GB and Grading British Coins, both available via that banner ad above. If you think you want to go further back, invest in a copy of Spink's Standard Catalogue, which lists most English types from Celtic and Roman onwards, and which becomes more comprehensive the further forward in time you go.