You need to add a registrant manually?
Although you'll try to get all of your registrants to use your website to register for your event, some will still want to do things the "Old Fashioned Way." They'll ask for a paper registration form, or maybe just send you a text message that says, "Put me down for a foursome, I'll pay you later!" No problem!
All you need to do is register that person on your website as if you are that person. So, go to birdeasepro.com/yourwebsite, and click the "Register Button." Add their desired item to cart, fill out as much registration info as you can, and you're done! Keep in mind, you can change a registration anytime you need, so it won't throw anything off if your registration info isn't 100% accurate at this point.
Here is a video which demonstrates this.