Phase one was from 91 - 94, phase 2 started on an m plate in 94 and ran until 96 on an n plate.
Wheels - phase 2 has the 5 spokes, phase 1 has the turbines
Interior - phase 2 has a revised interior pattern for the seats in black and grey. phase 1 had blue and yellow bits in the pattern i think. leather was an option on both phase 1 and 2 and is grey in both.
Exterior - phase 2 has rounded rear lights as oppsosed to the flat rear lights on a phase 1.
phase 2 has clolourcoded one slot front grill and colourcoded bits under the headlights, whereas phase 1 has black plastic and a 2 slat grill.
phase 2 has larger rounded bumpstrips on the doors whereas phase 2 has smaller squarer bumpstrips.
rear tailgate strip on a phase 2 is often referred to as having a carbon effect on it with the badges above it, whereas the phase 1 is grey plastic with the badges on it. the door mirrors are slightly larger on a phase 2.
the later phase 2's had airbag wheels where as the phase 1's and early phase 2's had sportier steering wheels.
heres a couple of pics to give you more of an idea the first is a cherry red phase 1 which belongs to clio_head, and the second is a naples red phase 2 which belongs to me. Hope this helps a bit
Phase1
Phase 2