Credit cards and debit cards are the most popular options to add to Google Wallet. That said, you can also add several other useful things -- transit cards, store loyalty cards, gift cards, movie tickets, concert or event tickets, gym passes, boarding passes, theme park season passes, insurance cards, company IDs, and even official IDs that you can use for TSA Precheck in some states.

Also: How to add your driver's license to your iPhone's Wallet app

With the app's photo feature, you can add any card with a barcode or a QR code.

There are two ways to add a card to your Google Wallet -- from the Wallet app or your bank's app or website. The first option is the most common. 

From the main screen on the Wallet app, tap "+ Add to Wallet" at the bottom. Choose the type of card you're adding -- payment, transit, loyalty, etc. 

If you're adding a payment card, tap "New credit or debit card." Either scan your card with the camera or type in the information manually. Once you've added the info, tap save. Google may ask you to verify your payment method through email or text. 

Also: Google Wallet will now automatically add your movie ticket or boarding pass

Additionally, some banks let you add cards to Google Wallet from the bank website or app. If your bank supports this option, you'll see an "Add to Google Wallet" or "Add to GPay" button when you log in. Tap that button and follow the instructions.

If you're adding a transit or a loyalty card, you'll have to choose from the list (not all transit options and stores are available). You can then log in to your transit or store account and connect your card.

You can use Google Wallet on any Android watch running Wear 2.0 and up, including the Pixel series, the Galaxy series, and more (as long as the watch has NFC). With Google Wallet on your watch, you can make contactless payments wherever Google Pay is accepted by holding your watch to the pay terminal. This is an incredibly convenient option if you're in a situation where you can't, or don't want to, carry your regular wallet. 

Also: Google Wallet now supports 40 more banks

Google Wallet comes preinstalled on some watches, but if that's not true in your case, you may need to install it yourself.

Making a payment with Google Wallet is simple. The app's home screen shows all your connected cards. When you're ready to pay, swipe through until you see the card you want to use. Tap on it, and you'll see "Hold to reader" below. That lets you know the app is ready. Hold your phone close to the terminal and wait for a check mark.

Using your phone or watch to pay for things might seem awkward, but it's convenient once you get the timing and process down. 

I've been saved several times when I left my wallet at home but had my phone. The technology is pretty reliable. The real convenience, though, comes once you move past payments.

Also: How to add your transit card to Apple Wallet

I recently added my family's local theme park season passes to my Google Wallet. Now, I don't need to deal with my wallet or even the park app for admission. Even better, if we're visiting the water park, I can use my watch to access our drink and meal plans, leaving my wallet and phone in a locker.

Additionally, I've added my alma mater's football season tickets to the app, meaning I don't have to log in to another app on each game day.