I'm sure everyone will have good advice here, but here's what I do:
Seems like every fitting/area is a bit different. I add grease until I see (or sometimes hear) it pop out of somewhere. Also seems like you get a "feel" for the process and can tell by how much resistance there is to pumping in the grease. On my FEL and backhoe, two pumps is usually enough to see something move. On U joints that I grease once a year, I want to see some grease come out of each of the 4 "corners" of the joint, then I wipe of the extra.
I use two kinds of grease: JD poly-urea (the green stuff) on most everything, and then JD Moly grease on the backhoe and loader pins, since it is better at high pressure shock stuff like those pins see. I'm sure others will have different opinions. Seems like grease, oil, R1 vs F4, and the value of a quick hitch are debates that will go on forever :laugh:.
We got a new JD 190C mower at the fire station two summers back. The person in charge of maintenance got sacked when I found out that nothing had been done to the tractor :nunu:. An entire season of mowing with no grease added to the mower spindles! It took 12 pumps get some resistance, and 15 to see the 1st sign of grease come out of the bottom of the spindle. I got new blades for it and was going to get the old ones sharpened but someone threw them out :banghead:. But, :focus:.
Also be aware that some fittings that take grease are kinda sealed, so if you pump in too much grease you can pop the seal. Others here have more knowledge on that stuff than I do, we'll probably both learn when they chime in.
So there's my take on what I do.
Pete