Under normal conditions, straight cables are 1-1 and crossover (uplink) cables are 1-3, 2-6, 3-1, 4-4, 5-5, 6-2, 7-7, 8-8.
Under some conditions however, this is not enough to make the cable carry error-free 100Mbit/s traffic. Very advanced cable scanners may complain about "split pairs", and low-quality switches may be unable to get a link pulse against low-quality network adapters.