Anywhere between $9,050 to $9,150 would be a great conservative area to entry a short position. In fact, I would say if you were aggressive and willing to take more risk, you could even start scaling in right now around the current $8,950 level.
The daily 200 MA is currently sitting around the $9,150 and should be a major area of resistance. Especially given that the RSI is oversold on the hourly and approaching oversold on the 4hr as well, I am doubtful the bulls will have enough to push through that level today. Furthermore, we have seen a nice rally in the last 3 days. Long that have been buying in from the 7.3k - 8k will be looking to take profits at some point, hence I believe if we are rejected from the $9,150 daily moving average; the drop could be rather violent.
Compound this with the fact that we will be getting the death cross on the daily in 3 days if the price does not rally significantly; this is one of the best opportunities for a short I've seen as of late.