1. Download a screen capture program like Greenshot.
2. Save a screen print of the completed send receipt from your wallet.
name the image after the amount, type, and destination, (i.e "Send Receipt to Jane Doe $25 ERC20 USDT from my Coinbase acct "
3. Save a screen print of the block that contains the transaction
(i.e "Send Receipt to Jane Doe $25 ERC20 USDT from my Coinbase acct Block version"
4. Copy and save the entire Block Hash number. Paste it onto the screen print using the Greenshot or another picture editor that lets you insert text.
5. You have properly documented your crypto transaction so that if there is a problem you have proof of what you did.