A good strategy is to sell coins that will go down first and buy them again when prices start to fall. This requires good planning and proper analysis of the coins that will fall, making a buyback at the lowest price will add to the coins you have.

Altcoin is the best in my opinion is to buy some ETH because the current price of ETH is around $ 114. ETH has a good future with technology that has always been developed by its developers. ETH is able to offset the price of bitcoin. I only recommend ETH, if you have another altcoin option, first make sure the coin has good technology with developers who are always active.