One other thing I've encountered is that it is important when calling up to give a pilot report that you call out to the relevant flight service station or Flight Watch. I had a situation flying from LA to Oakland once when I was somewhere over the San Joaquin Valley, tuned to 122.0 and called "Flightwatch, Cirrus Niner Zero Seven Delta Romeo with a pilot report."
What happened next was that I got two simultaneous replies - one from LA Flight Watch and one from Oakland Flight Watch. LA was hard to hear and at first I didn't realize I was talking to both. Eventually, LA got pretty annoyed.
So, now I make sure I know which ARTCC I'm in and my call is to "Oakland Flightwatch" or "Seattle Flightwatch" or whomever. The same is true with FSSs. I believe the correct call would be "Rancho Radio" or "McMinnville Radio" to call the flight service station.
When on an IFR flight plan you have to ask permission to go off frequency to give a Pirep. Usually, they will tell you to report when back on. If you have VFR flight following, it's also a courtesy. So, that would be: "Norcal, Cirrus Seven Delta Romeo, requesting frequency change to Flightwatch to give a pilot report."
When flying in the boonies, you often have to wait quite a while in order to get a response, so be patient. If you have a radio that allows you to monitor one channel while talking on the other, it's probably good to do so, especially if you're getting flight following so that you could hear any traffic call-outs while you're waiting to talk on the Flightwatch frequency.
Hope these observations are consistent with what our CFI hosts would say. If not, please correct.