1. How much time does it really take to skill?
Surprisingly, a lot of experienced players assume that skilling up to three levels is a time-consuming burden that has to occupy hours a night. Done properly, this is absolutely not true. Even four maxed levels should not take the majority of your play time. There are three tips below that should minimize the time necessary to gain up to three full skills and maintain them. These techniques were developed in beta before variable skill locks and they still work like a charm. Now, five or six maxed skills, like Mount Everest, take a little work and a lot of skilling but that's for people who want to do it just because they can. That's another story and not what this article is about.

2. With Variable Skills Locks, is there any point to skilling past my lock level?
That depends. Up to 30 additional locks are obtained every 21 days. However, these locks only become significant in two cases: (a.) Nine locks a complete set of gift emotes and interactions, if interactions is a goal, and ten locks a maximum skill level available, if money-making (or maximum promotions in the new Jobs tracks) is a goal. (b.) Lesser numbers of locks are primarily useful for preserving lower level skill, or simply maintaining a skill that you intend to promote later. Because of the skill decay rate at lower levels, the existence of one or two extra locks won't help you skill up a bit. They will allow you to have an emote or cook better. Considering it takes 210 days to have a totally safe second skill lock, it takes some time to move up relying on variable skill locks alone.

3. What factors affect my skill decay?
There are basically three factors which affect skill decay.
(a.) Total Skill points. The more total skill points you have in ALL skills, the faster your skills decay. This is not a big factor in people with two or three or even four skills, but it makes five or six skills a real challenge. For most Sims who have three or four desired skills, this is not a killer.
(b.) Your mood affects skills. The worse your mood, the faster they decay. If you go to a boards-till-you-drop contest and compete until you are totally red or allow yourself to AFK until you drop on the floor, your skills will decay MUCH faster than if you stay reasonably green. This is a noticeable factor in all Sims.
(c.) THE MOST IMPORTANT FACTOR IN SKILL DECAY, AT ALL LEVELS, IS SKILL LEVEL. This is the secret of skilling basically, which is logically totally backwards in TSO than any real world person would expect and the real factor that allows skilling techniques to work. Unlike real life, TSO skills decay slowest at the highest levels. No real world person would expect to be able to retain the ability to do back flips on a bicycle longer than the ability to ride on sitting down on a flat road, but this is exactly what happens in TSO.

4. How do I get the desired number of skills in the minimum time?
Follow the following three steps:

The idiot simple technique
1. Simply put, manage your skilling time to interfere as little as possible with your gameplay and vice versa. Frankly, I'm a pretty irresponsible Sim who likes to visit and party and do a fun contest once in a while and this hurts skills, BUT there are a number of things that help. For example, take a nap, use the toilet, and join a game of pool while doing any activity before you go totally red. If you are busy and aren't devoting your total attention to the game, go to a skills lot and do it there. Most don't mind. Once again, I've made a lot a friends at skill lots and I try to be at least half there and willing to talk while I'm at it, but if you don't feel social, AFKing your time away at a skill object at 118% is a lot better than sitting at your lot watching the plasma TV. Timing out at a skill object is a way of life for some, so if the pets are put away and you've said your goodbyes politely, just spend that fifteen minutes while you're in the shower getting ready for work or dinner with the in-laws playing the piano or reading a book.
P.S. Leave the owner of the skills house or the current roomie 240 Simoleons to load the buffet twice, more if you sat there for three hours or got some nice treatment, okay?

A little tougher concept
2. Skill Approach Management. Don't for one instant imagine that going to a Cooking lot to get four skill points is going to do you any good at all. At the skill decay rate, depending on your total level of skill, those four points of Cooking will be gone in three days, two days, or before you can whistle Yankee Doodle. Low levels of skills decay fastest. You want to be social and help a friend learn Cooking while you are chatting? Fine. But you'll never keep a skill that way. Simply put, if you want a second, third, fourth, fifth, or sixth skill, plan on getting it to 10.99 in two or three days of planned time or forget about it. This is what happens. If you spend two solid nights getting a skill to 10.99 and forget it for three days, you will still have a skill at 10.04 when you remember to look and it will take you a half hour a week to keep it there, on the average. If you get a skill up to six or even seven and forget it for three days, you'll wind up doing it all over again, forever, and it will take you ten times as long skilling to get nowhere. Trust me, it's true. Go for the top all at once and it will last ten times as long. Secondly, the lowest decay rate occurs at 10.60 and up. If you see a skill that you want to keep decay below 10.60 then go refresh it for half an hour. It will be the LOWEST possible time you can spend on a skill at any level in the game.

The real secret
3. NEVER LOCK YOUR HIGHEST SKILL!!!!!! This is the biggest skilling mistake you can make. The lowest skills decay fastest, totally unlike real life. In a screwball universe you need to use screwball techniques. The skill to lock is ALWAYS the LOWEST skill you are not currently working on. Think it over. By locking the lowest skill you intend to retain, the one you are NOT now enhancing, you will experience the lowest possible rate of decay. This technique is the most important tip of all. It may seem weird, but give it a try.

The techniques described above, like the famous Code chart, which might not make sense to the average person on first glance, were discovered in beta testing, by skilling specialists like the Men In Black in Test Center and they work unbelievably well if done well.

The most important thing to remember, though, is that THESE TECHNIQUES WORK EQUALLY WELL FOR SOMEONE WHO ONLY WANTS TWO SKILLS AS FOR SOMEONE WHO WANTS SIX. Believe me, having three maxed skills is a non-time consuming, minimal effort enterprise and even a nice way to get to know some Sims at a skills lot.