I try to sail on, and off, my mooring. Admittedly, I do not have other boats near me, and so, why not? One thing I have picked up from this may be of use. When under power, I approach the mooring ball the same as I would under sail. I refer to speed and set/drift here. As a result of this approach, I always have my lunch hook made ready. When the engine fails, or the prop is fouled, you'll be in the same situation as if you came in under sail-without the sails to bail you out. The sail area of the boat alone is enough to ruin your day in that situation, having an anchor ready will allow you to regroup before you're aground or swapping glass.
I prefer picking up from the bow, single-handing, if possible. All the bad things that can foul are aft of midships. Mis-judging your approach, and realizing it while on the bow, means back to the cockpit for adjustment or another approach. Mis-judging while trying to pick up from aft may mean getting blown down across the mooring and fouling on keel or worse. But it is sometimes the only way to do it while alone.
An idea not mentioned yet, and rarely seen done for reasons that escape me, is making a pass through the mooring. A dry run, if you will. Motor on in, cut the motor where you think appropriate, and see how she handles. The unseen tide may be doing things to you that the visible wind is not. If everything is going "just ducky", hook the mooring and be done with it. If things are looking a little squirelly, make a mental note on a different approach on the next pass. Too many make the mistake of thinking they're Sir Francis Drake picking up his mooring off the Lizard with the monarch watching. The minor caution involved in a couple of passes is nothing to the chagrin felt when things go really bad, as illustrated by TrueBlue's experience.
The bleach bottle idea is excellent. I would put it on a cement block or something, and leave it out. Then, each time you go out, you can stop on the way in and pick up your "mooring", under a variety of conditions. IMHO, this will give you a lot better practise than just spending a whole morning under static conditions will.
I second the opinion of practising alone. Another person along, even just standing by the anchor, will make you behave differently. Maybe the first couple times, but then ditch them and practise on your own.
“Scientists are people who build the Brooklyn Bridge and then buy it.”
Wm. F. Buckley, Jr.