Apply 2-4 times a day and make sure 2 of those are before bed and upon rising.
Our Atrogel® is not a rubbing oil, so it doesn't take long.
It performs as well as a 5% ibuprofen gel (the strong one) with fewer side effects, so you should find it good.
You may wish to add something that works on the inside too.
If you take Atrosan® Devils Claw, just be a little patient as its effects build over a few weeks and if you want to nourish the joint with Glucosamine, you'll have to be a little more patient again as the knees are always working hard and you might have to think in terms of 3-4 months for benefit.