I just hold, everytime I tried to play the market I lost some coins.
Buying is just like investing but it's just gaining a profit through holding what you buy in low value and sell it when it is increasing. That's everyone idea to have an income.
The best strategy is to buy at lower price then sell it at higher price and once the market will recover you will gain profits if you have patient to wait for the best price. Remember don't sell your coins at losing price and you need to trust your coins that it will bounce back soon.