Emmie....choose your potatoes carefully...buy King Edwards if you can.
After peeling, par-boil for about 10 mins in salted water. ( take no notice whatsoever of those people that tell you not to salt the water )......Drain.
Then put them back into the saucepan, put the lid on firmly and give it a good shake, until they are "fluffy" !
In the meantime, you will have heated up a tray of oil, or lard
( my guilty secret is a mixture of lard and olive oil )
Carefully put the spuds into this tray of hot fat...wish them around a bit and then put them back into the oven, on a fairly high heat. If you put some of the fat from your roasting meat in as well, all to the good.
Then cook until nice and crispy....enjoy !