Many methods out there in the world, this is my preferred method:

Materials used:

Golden GAC 400 (fabric stiffener)
Golden GAC 100 (resists oil penetration)
Golden White Gesso
https://www.goldenpaints.com/technicalinfo/technicalinfo_gac100s
https://www.goldenpaints.com/products/gesso-ground/gesso

Canvas and stretchers usually purchased from: https://www.russellandchapple.co.uk/ This company provides a variety of canvas weights and a good selection of stretcher bar thicknesses.

To prime:

• Begin with 1 coat GAC 400 fabric stiffener for sizing the front of canvas (I normally also continue around the sides with all coats). The GAC 400 tightens the canvas on the stretcher and it is not hygroscopic when dry (unlike traditional rabbit-skin glue). This is a great first layer on the canvas, bringing it to drum-like finish.
• Once dried for 24 hours apply a coat of GAC 100, wait 24 hours and apply another coat of GAC 100.
• When GAC layers are fully dry apply at least 2 coats of Golden White Gesso. This gesso will bind well to the GAC 100 and will allow both oil and acrylics to bind well to the surface. When coating the canvas with multiple layers of both GAC 100 or gesso, it’s a good idea to vary between horizontal and vertical strokes for even coverage. Allow to dry sufficiently before painting.