First of all, try calling out to your angel. Just say "Hello, angel!" and alert him or her to your presence. It may feel a bit silly at first, but rest assured, this step is very important if you wish to connect.
Secondly, just as people have names, so do angels. Ask for this information, out loud to your angel. Simply say "What would you like me to call you, Guardian Angel?" or ask for his or her name. The name may pop right into your mind! If not, think about it for a little while. The name will come to you. If you've tried this over the course of a few days and there doesn't seem to be a name that "pops," I'm sure it would be fine to name the angel yourself. The right name will come!
It's also important to discuss your needs with your guardian angel. Don't abuse the privilege of having this protector, but feel free to call on him or her if you need some assistance. For example, if you need help finding a lost object or you're waiting for a phone call, there is noting wrong with requesting some help. State your need clearly and specifically, i.e. "Angel, I request your help in finding my car keys." You get the idea! If you're seeking help with something more complex, such as a new line of work or the meeting of your ideal soul mate, be patient for these things to manifest. Your angel does not want you to make the wrong choices, so you must understand that the perfect outcome will occasionally take time -- sometimes quite a long time -- but hang in there. Your angel is tirelessly and lovingly working on your behalf. But remember, unless you're in a dire situation, angels can't assist you unless you ask for their assistance!
While guardian angels serve humankind lovingly and joyfully, it's also important to help others as well. Keep the cycle of giving going. You needn't be rich or powerful to give -- the most important gift is the gift of yourself! Help a neighbor in need, volunteer your time, or make even a small donation to whatever organization that you feel will do the most good. Always seek ways to help people. Giving of yourself is beneficial for other people, and it also makes you feel great.
Above all, remember to keep the communication going. Connecting with your angel will take practice, so don't give up!