Kiwi grip goes on with a trowel. It looks a lot more like paste or mastic than paint. One then rolls a specific roller on it. I used what looks like a 4 inch roller and had no real problems getting the texture right. You tape the section off, trowel it on, roll it, and immediately pull off the tape. The directions suggest a second coat, thinned out some, if you want less aggressive non-skid.
I hose out the bottom of my cockpit and that typically takes care of it. I have used a boat brush to scrub it some in the past; it did not see that onerous.