place him gently into a high sided box using gloves or a towel if you are deterred by the prickles
 

a hot water bottle wrapped in a towel will provide life saving warmth whether he is suffering from hypothermia or shock - but leave room for him to move off the hot water bottle if he feels too warm.  He must have direct heat, a radiator just isn't sufficient.
 

check very carefully that flies (blue bottles) haven't already laid their deadly eggs in his ears, eyes, mouth, bottom, armpits or anywhere amongst the fur on his face or tummy.  These eggs will quickly develop into maggots that will eat the hedgehog alive.  Artists' paint brush, tweezers, cotton buds, nit comb and magnifying glass are all useful aids for the meticulous removal or eggs or maggots.
 

Never use dog flea spray on hedgehogs - it is lethal.  Johnson's Rid Mite or Johnson's Cat Flea Powder (from pet shops) is best.
 

Offer cat/dog food, we use Whiskas.  DO NOT feed pork and DO NOT feed bread and milk.  Lectade (from the vet) can be dripped from a dropper or syringe if the patient is too young or weak to eat meat.  Further persuasion to swallow can be given by tickling his pallet with a soft paint brush dipped in Abidec (from the chemist).
 

The hedgehog must be kept warm at all times
 

Cover him with something woolly, protect him from flies, stress, noise, light children and pets.
 

Inspections may also reveal bean-like nodules, which are ticks.  Careless removal can leave the head in the skin to cause an abscess so paint the parasite with vegetable/cooking oil to suffocate and release its grip
 

constant warmth is essential for his survival.