First of all welcome to FF.
Regarding to the heating, if it's a glass tank a heat mat under neat the tank can crack the glass. If it's a plastic tank you can use it underneath. Since it's a terrestrial frog(means that lives on the ground) I don't know if you can put it on the side. The heat bulb is good too. You must make sure to connect it to a good thermostat and make sure that the tank holds the humidity when the heat bulb is on.