By being aware of your body. When you start to huff, puff and pant, slow down. Make yourself slow down. Then slow down some more. Your body will get used to the right pace if you show it the right pace.
Remember that YOU set the pace. If you learn to do this now, it'll come back to help you in the future. Even now, after 2 years of running, I use my pacing to get stronger and go longer.

Keep trying. Don't give up. You're going too fast but you're a step ahead of many other runners: you KNOW you're running too fast, many don't know this. Therefore, you CAN make that change in pace.

Let us know how you do on your next run. Listen to your body. You're going to do great.

Hmm just a thought - any way you could use a treadmill somewhere? Even if you don't have a gym sometimes if you say you're thinking about it you get some free passes... Or maybe someone you know has one you could use a couple times? I far prefer running outside but just thinking if you set a certain pace on the treadmill you are forced to run that speed - maybe just a few times would give you the feel of it then you could head back outdoors

Do you run with music? There are a bunch of downloadable podcasts that play music that are all the same bpm. I found it helped to run to the (slow) beat when I was first starting so I didn't go too fast.

I listened to painfully slow music. Then my dog had surgery and rehab for her back leg so I ran slowly following her pace. It taught me to lengthen my stride a bit and concentrate on form and now my calves don't ache so much.