The analysis is based on a channel wave C is currently moving in and the fact that wave C is missing it's last leg (5th wave).
If wave 3 = wave 5, then we end up at around $2900. If 5 = 76.8% of 3, then we are heading to around $4200.
This is by no means a buy/sell signal. I am just a noob at trading, so please do your own research.