Draft
Select the body, click the faces to be tilted, point at the neutral face, set the angle, press Enter.

What the neutral face is
It is the face that does not change: the tilt is measured from it. Usually it is the parting plane of the mould — the way the part sits in the tooling.
What it is for
A cast or moulded part will not come out of the mould without draft: the walls must open slightly towards the parting line. Typical values are from half a degree to three, depending on the material and the wall height.
Order
Draft goes before the fillets: a fillet on a drafted face comes out right, draft on a filleted one hardly will.