1. Create a Coinbase account
Download the Coinbase app and start the sign up process. You will need a valid ID and may be asked for proof of address in order to transact, so be sure to have those ready. Verifying your ID may take longer than a few minutes, depending on where you live.
2. Add a payment method
Tap on the payment method box and connect a payment method. You can use a bank account, debit card or initiate a wire.
3. Start a trade
4. Select API3 from the list of assets
Search for API3 by typing "API3" into the search bar. When you see API3 show up in the results, tap it to open up the purchase screen.
5. Enter the amount you want to buy
Use the number pad to input the amount you want to spend in your local currency. The app will automatically convert that into a API3 amount.
6. Finalize your purchase
Tap “Preview buy” when ready. You’ll be shown the details of your purchase. Make sure everything looks good and then confirm your purchase. That’s it, you’ve bought API3.