We need to see one of the following scenarios to confirm C wave has bottomed
1: We have a clear iv wave followed by a clear wave v down. So far, the bounce today does not feel like it is a iv.
2: Sometimes, you just wont be able to see a clear structure due to market's extreme volatility, in that case, we need to see a bounce from whatever low to go above 0.618 Fibs (measured according to the length of iii wave). Until index can climb back above that level, it will turn around and go to another low
This was exactly what happened when QQQ was 494 2 weeks ago (rejected at exact .382), and QQQ 480 this week (rejected at .618).
The normal region for this C wave should be 4900-5100, but we are not in a normal market, so, need to pay attention to the actual movement.
Now, how you trade is totally up to you. Someone is comfortable with left side trading, and others comfortable with right side trading. This is something you need to decide for yourself