Along the same line as what Carol said..You can also hold the long longe line (use a piece of light weight clothsline with a clasp tied on the end) make sure it is long enough to give your dog room to wander off. You hold onto the one end, have good treats ready. When your doggie starts to wonder off away from you, you begin to run backwards in the opposite direction and with a very happy voice say...Lola come, you need to be very excited and make it fun..try not to repeat too many times..if she comes to you..good girl, treat. Then do it again, let her wander off..and start over. Maybe do this for 5-10min. at the most, do it daily several times a day. The goal of course is for her to eventually "come" on command off leash. This is the way I've trained all three of my dogs, they are all 99% at coming to me no matter what. I would never give a dog 100% as I don't believe in it, there will always come that time when the squirrel or whatever seems better then the "come" so be prepared always.
Kathy