some suggestions one can safely ignore

From Golfing at "Niknar" (Pearl Municipal Golf Course)

Unless you're ultimately preparing for tournament play with USGA rules or similar, your solo rounds of golf can be an endless series of "practice rounds" played with very loose interpretations of the Rules of Golf. Just don't file a scorecard for handicap purposes if you didn't follow the rules to the best of your understanding. (If you report artificially lower scores because you didn't impose penalties and deal with the harsher realities of "real" golf, you'll take a beating when you do eventually play with others who expect you to be a stronger player than you are.)

Some penalties don't seem strictly necessary when playing a casual round alone. For instance, the rules of golf require that you take a penalty stroke if your ball contacts the flag stick under some normal circumstances. When playing/practicing alone, penalties like this one don't seem to add any value to the game.

Bring a little cash for the pro shop and grill. They may take plastic, but the credit card processing machine can be down, or you may encounter a tip jar. Better safe than sorry.

Pick up a spare glove. Some times it's hard to keep a glove dry. A second glove can help keep the comfort level up. I even use one glove for each hand under certain circumstances such as cold weather.

If you're not a pretty good golfer, consider using forward tees for practice rounds. I'd rather score a bogey from the senior tee than lose 3 balls in the water from the "real man" tee.

Keep pace. Try not to delay the group behind you. Playing solo, you may find yourself overtaking the group in front of you after several holes. Golf etiquette provides simple ways to make these situations work out.

It's okay to be a terrible golfer. Almost everyone out on the course is also pretty bad. The guys you see on TV golf doing miraculous things are earning a living at this because they really are in a different class of performance, so don't compare yourself against Tiger Woods.

However, if you're going to be an enthusiastic golfer, take some lessons as soon after taking up the game as you can. You'll enjoy the game much more.

Consider practicing "best ball" and similar variants while on the course. Instead of waiting endlessly for the foursome ahead of you to get it together, hit two balls off the tee and either play the best one or go ahead and play both.

Instead of searching the woods for lost balls, you may want to stock up on the cheapest balls you can find and dropping a substitute ball after a reasonable search effort (Environmental considerations may discourage this in some cases.). I personally prefer orange, yellow, pink, or otherwise bright & easily spotted colors.

If, when you make it to the green, you see pitch marks from balls hitting the green, try to repair them on your way.