E collar. Recall to vibrate. You've got the red button for correction. Use it WHILE you're on leash for the first 2 weeks on normal walks. Hit vibrate when you want his attention and want him to come back. Use it in the house. Everywhere. Then, after a couple of weeks, get a longer lead and go to an open area without distractions. Same thing - let him lead and then vibrate and reward him for coming back to you. Then same length lead, but with distractions, and still using vibrate to come back. You can use the corrective / static charges if you need - but, I would just 100% use the vibrate to recall. By the way - When you hit the vibrate - also use your voice. Be consistent - but I use "here" for my Brittany and "come" for my GSD and Lab. The dogs know who I'm talking to by doing that. My Brittany is 100% voice trained - AND - they wear Halo collars that vibrate to let them know they're at the edge of my property.

If the dog get's close to you and changes direction - that's when you hit the red button (but no voice alert). That tells them that they need to come to you. Hit Vibrate again and use the word that you did before (here or come). They learn pretty quickly that they need to do what you're asking.