Well, i suggest you, most of the sites are scam, But not every site, and if you want to invest your bitcoins into any cloud mining site than only search about it and may be your friends are doing it than you take help from them, and if you get trust-able mining site than in the start invest your litter amount.
yes it's true that currently is very difficult to find real legit cloud mining sites but doesn't mean all of cloud mining sites are scam but just be carefull to those sites which is offering big profit to their investors because usually they are scam and as far as i know that legit cloud mining sites only offering small profit for their investors but for long term only