heat and humidity questions

My little grow box is at around 80 degrees F. is that about right? And what is a easy way to get the humidity up? its a fairly small area. 4 ft long 2 ft tall

1, A $14 VAPORIZER from Walmart will fog it good.
2, MIST them daily with plain water.
3, Place Saucers of water and wet rags around.

thanks for help roseman