I would suggest you to buy something like 5 bitcoins when the Bitcoin price is 280 USD, and sell 4 of the coins when the price is around 350 USD,
5 X 280 = 1400
4 X 350 = 1400
so you will get 1 btc free of cost.
the big question now is when will the price of bitcoin go down to 280? you can't just say things that unlikely to happen right now
Nobody can answer that, only thing we can do is speculate about when that will happen.
I really doubt it will go below $300 again though. We've been at around $300 for 2 weeks or so now.
I believe it will either stay around $300 or it will go up.