A glass enclosure with with mesh top, sand or coco fibre or a mix of both as substrate and for heating a heat mat will suffice.
If you get a terrestrial gecko put the heat mat under the enclosure, for an arboreal gecko stick it to the glass on the back of the enclosure.
Aussie geckos love small dark spaces so little hides you can buy are great or do what I do, make them using rocks and use wet sand to hold it together, when it dries its like concrete. I've done this for year and never had a rock fall off.
Being nocturnal you won't see them much during the day so if you wan to see them at night, see what they get up to, get a low wattage moonlight bulb. Hope that helps.