Trust wallet is my preferred mobile wallet because it is sponsored by binance and offers good possibilities for the staking of various altcoins, of course I keep my passphrase very well a copy I have it on my computer and another copy i kept on a piece of paper.
It's very easy process. Download the official Trust wallet app and just follow the procedure one by one and you can easily create your wallet account. Only important thing is that, you must do a backup of your recovery phrase because if in future you somehow lost your private key the you can recover your wallet account by this recovery phrase otherwise you can't recover your account.