I was taught the following:
1. Join at 2000 feet above the airfield
2. Position yourself so that you're crossing the runway threshold (? that doesn't look like the correct spelling) still at 2000 feet on a base heading towards the deadside
3. Once on the deadside begin descent and a 180 degree turn to end up on the crosswind leg crossing the upwind end of the runway at circuit height
4. Fly the crosswind leg until in a position to turn downwind still at circuit height, and slotting into any traffic already in the circuit.