As NoMercy indicates, hardly any airlines (and certainly no UK budget airlines) issue printed tickets. You just need your booking reference. See here:
http://tinyurl.com/ybfuayz
If you check in at the airport you've got two cut-off points to remember. The first is that you must check in at least 40 minutes before the flight departs. The second is that (after getting through security) you must present yourself at the gate at least 25 minutes before take-off. In practice, the first cut-off point is the important (rigorously enforced) one. The second one can be much less important. (You frequently won't even see any easyJet staff at the gate until well after it theoretically closes).
If you check in online (which you can do right now) you can ignore the first cut-off point if you've got no hold baggage. You print your own boarding pass and then, on arrival at the airport, go straight to security and on to the departure gate. If you've got hold baggage, you take it to the fast bag drop which (like check in) closes strictly 40 minutes before take-off.
Unless your booking confirmation says otherwise,easyJet advise arriving 2 (not 3) hours before departure. That should provide ample time.
easyJet's boarding policy is here:
http://www.easyjet.com/EN/Flying/boarding.html
In common with other budget airlines, easyJet aircraft are basically'buses with wings'. i.e. you find your own seats, exactly as you would on a bus.
Chris