It's a volatile and risky investment.
1. You may select a wallet which is separate from the purchasing platform. e.g. Jaxx.
2. My preferred method is www.coinbase.com which has an android and iOS app by a similar name.
Confirm your email address and your phone.
Set up authenticator (download Google Authenticator, for example).
You're likely to encounter verification hiccups because they seem to have problems handling the volume of traffic.
A credit card would do. There's a limit, which is good to prevent excitement.
And I view my portfolios in one place.
Even 10€ worth is doable.