Anytime is good for investment, there's no fixed time for investments, crypto world any one can get in at any time, so for that my first advice would be for you is to invest in Bitcoin, then use only electrum wallet, and never disclose your private keys and seed to anyone. Buy in small quantities say you have 1000$ to invest keep investing 200$ or less amount at intervals, when it's down more and High less. Remember there are fees per transaction buy and sell so check it out. You can invest any amount, just remember there are fees per transaction.