Cat Rescue and Adoption - Sheffield - Wizz Catz

That may or may not be helpful. I would keep him in for more than a few days. Maybe 3-4 weeks, so he gets used to the smells, sound of your/family members voices, noises.

Before you let him out, I suggest putting some used litter (not poos!) in the garden at various points or hoover bag contents. This would help him know where his territory is (got this idea from the 'missing cat' points where it suggested that and spreading the content of the hoover bag, so the cat can 'smell' where home is.)