I'm new to BPs and have a few questions.

Firstly I'm considering getting the Exo Terra Ceramic Heat Emitter 100W, can I use this on its own or do I also have to use a heat mat?
If I do use a CHE what's the best bulb guard?
I'm also slightly confused about thermometer placement, I'm going to use a thermostat for the CHE, but do I also need a thermometer for that side (hot side)? I know I need a thermometer for the cold side (correct me if I'm wrong). Where does the hydrometer need to be placed (any suggestions for an accurate one welcome)?

Thanks.