between the hot and warm setting you will see a small vertical bar. Line the up with the RED mark on the outside of the dial. One other thing is you should hear the main flame make a slight roaring sound. If not it could be that the orifice may be slightly clogged. That tends to happen if spiders etc. get into the burner.
2004 Jay Feather 25E
2001 Ford Expedition 4X4 EB 5.4 3.55 rear
2004 Ford Expedition 4X4 EB 5.4 3.73 rear