2FA (Two Factor Authentication), obviously. It adds an stronger layer of security to an account. Though it is never recommended to keep your funds in a wallet that is mainly used for exchange purposes, but even if you do, it is always good to have all the security features active for your account. I would suggest you what @OmegaStarScream have suggested already. Either buy a hardware wallet-- if you think you have a lot of funds to be stored securely, or just use a desktop wallet like Electrum, Bitcoin Core etc since they are more secure than any online wallet.