A glider flies just the way any other plane does: the wings provide lift to keep it airborne. The controls – elevator, ailerons and rudder – are the same as for any aeroplane. A glider has to fly downhill all the time because it doesn't have an engine pulling it forwards – much like a bicycle freewheeling downhill.
For a glider to go upwards it has to fly in rising air, or “lift”, and that's where the fun starts. Gliding is all about reading the sky and seeing where the rising air – free energy – is. If you get good at this you can go surprisingly long distances surprisingly fast. Some of our members regularly fly 100s of km across Scotland at average speeds of over 100 kph. Here are some photos of a nice 425 km cross country flight around Scotland.
If you want to know more about how gliders fly and soar, there are loads of excellent reference materials. There a short introduction to the different kinds of lift we use here.