First I hope you bought the phone with cash. If not, you should have. Same goes for the cards. Use cash to buy them. The phones usually have an option to activate online or by calling a number. You can activate and register the burner phone using any info you want from any state you want. If you activate it online use your alias email as the email for updates and to get back into your account should you misplace the password.

I don't use a burner anymore but when I did several years ago, I got a card. Then I picked an area code of the most rural state that I could find -- North Dakota. I called in, the area code was not available so I picked one in South Dakota. It happens to be Sioux Falls. The kid on the phone couldn't even pronounce "Sioux" correctly

1. Go to Walmart, get a "Tracphone."  You can sometimes find these elsewhere, such as Walgreens, but Walmart always has them.  Pay cash.
2. While there, buy a Tracphone minutes card.  Also pay cash.
3. Call the number indicated and activate over the phone.  You don't need to log in from a computer or use an email.
4. Hobby

Selecting a burner isn't so much of a challenge as much as making sure you leave no trail. My 2 cents similar to what's already stated...

Pay cash for all transactions regarding it.
Use your "alias" accounts on the device.
Make no credit card transactions on it.

Use TOR for all accounts tied to it. (Google TOR.) That is, if you put a gmail account on the burner device, login into that account using TOR if you're on another machine / device. This keeps your main home IP address / main device from being tied to your alias account.  

My super paranoid advice... Do not bring your main device with you when on a date. Keep the main device and burner separate as much as possible in terms of your geo location. The location of both devices can be tracked together. I admit this is going above and beyond, but the super cautious side of me enjoys the whole "clandestine" side of the hobby

when you are buying reload cards check the terms on the back. I recently bought a card that ended up expiring in 30 days. when I went back to get another card, I found there were cards that were basically identical, but the 30 day one I think included data, and there was another on for the same face value but it lasted 90 days. It was pretty annoying to be on my way to a date and find my burner had no minutes! I was dashing through WalMart like Guy's Grocery Games for a quick reload!