The first thing I would do is check the water level in the radiator. Is it up to the top and is there plenty of coolant in the overflow tank? Also, now is a good time to check the condition of the Radiator Cap. If that'* OK, go out a get a new 195 degree thermostat and gasket and replace the existing thermostat. Make sure that after you install the new thermostat that you bleed the system. That is, getting rid of any air that might be trapped in the engine. Usually just running the engine with the radiator cap off for a few minutes does the trick. If that STILL does not provide adequate heat then it could possibly be a clogged heater core. But I'll defer to the guru'* of know-how to tell you other things that you might need to check.
2006 Salsa Vibe
2002 Snap Orange Beetle - Turbo
1991 Olds "Orphaned" 88 - Donated to Science!