Here are some examples of themes to select from: bride and groom, bride and groom pop-out, beach/ fish/ seashells/ tropical/ nautical/ island, Disney, seasonal, floral, hearts, holiday and Christmas, Las Vegas, leaves, modern and unique, snowflakes, forests, and nature, and beautiful abstract modern art designs.
You can even specialize the following order addition when you first get one: invitations & envelopes, return address on envelopes, reception cards, respond cards, informal cards, and shipping method.
Before you jump in though, get a good look at the choices you have before you on Google. There are at least 15 sponsors for wedding invitations, and you need to give them all a shot. It should only take you 20 minutes to look through them all. Have fun, stay cute, and pick the right ones for your amazing wedding today. It doesn't take much time if you have a friend or a spouse helping because, sometimes, an outside perspective is all you need. It's hard to do it all alone.