I think working at liberty with your horse is one of the best things you can do, especially for improving your relationship. I start by just playing with my horses and hanging out in there paddock, making sure that they enjoy my company. I do a lot with them on the ground in a halter, but I make sure that their work stays very varied so they never become bored. However, if you have a nervous horse who likes to run repitition of the same exercises can be a great way for them to settle down and relax, whereas a slower horse with less 'go' will often quickly become bored with doing the exercises over and over again. Once your horse enjoys your company and respects you as a leader then he should follow you around without a halter, but for doing finer points of liberty, I will train them with just a halter on or other VERY basic equiptment, and train them to respond to the lightest of cues, which starts with body language. Once this is established it isn't such a big deal to remove the halter and continue doing the same thing at liberty. Practise disengaging your horses hind quaters, this way if when at liberty your horse should try to walk away from you, simply disengage the hindquaters until they are facing you again. Always start with liberty in an inclosed area should anything go wrong, and remember to ask for little bits at a time, and remove any pressure as soon as they respond in a positive way.