I'll be sealing some cracks on mine soon--first, I'll paint them with this stuff or similar ( non-rubberized asphalt-based emulsion) then I'll sweep sand /fine crushed rock into the wet crevices, repeating as needed which is pretty much how we did it back when I was a pavement specialist in the Air Force.
For larger patches, we'd cut away a fairly good sized area, usually a square foot minimum, so that the esges were nice and thick for bonding purposes and so the base material underneath could be re-leveled, wetted and tamped--then, we'd brush the emulsion ( SS-1 slow set ) onto the edges and bottom of the hole, fill with cold patch and finally we'd tamp it down flush with the surroinding pavement....IIRC, we'd fill to an inch or so above flush, and we'd tamp with tool that was made from a piece of ~3/4 in thick steel plate about 8x8 inches that was welded to the bottom of a piece of 2in diameter pipe that eas used as a handle...if you want to get fancy, you can weld actual handles onto the pipe, a pair of rebar grab-handles was typical....
--the patch material will want to stick to the bottom of your tamper; if you dip it in diesel every so often, sticking shouldn't be a problem but if it starts sticking you can usually scrape it loose with a flat bottom shovel....IOW, a 5 gallon bucket filled about half full of diesel is a pretty handy thing to have around if you happen to be out patching asphalt.