If you have more experience than education, next should be Experience, sometimes also called Employment History, Work History, or any other such phrase. (If you have more education than experience, put that first.)
This should be a list of the jobs you've held (for a "chronological" resume) or things you've done (for a "functional" resume). Which of these should you do? A chrono resume is far more standard, and generally preferred. However, if there are embarassing gaps in your employment (such as long unemployment due to lack of skills, being in prison, etc.), you may wish to use a "functional" resume, which omits much of the data about who you worked for, when, where. A functional resume helps a reader find out whether you've done some particular thing, but it is a Big Red Flag. Don't use it unless you have something to hide. All further advice will be for chrono resumes.
A chronological resume should be in reverse chronological order (i.e., most recent first). Each entry should be laid out in a logical orderly fashion (just like the whole thing), and contain:
(It is debatable whether the dates or title are more important, but it's generally agreed that they are the top two. I prefer date-first so that the "timeline" is obvious. If you have embarassing employment gaps, but don't want to use a "functional" resume, you can hide the dates behind the title.)
All things above here should be in a nice neat consistent format, rather than just running on and rewrapping wherever the margin hits. If they will all fit on one line each (very difficult to ensure on the web), fine, otherwise, you will probably have to insert a line break. Make sure you do this at the same logical point on each job!
You do not need to include details such as your supervisor's name (he may well be gone anyway), salary history, reason for leaving, etc.
You may use different typographical effects to distinguish parts, but as always, be consistent and don't overdo it. (If you're putting your resume on the web, remember general HTML style, and avoid underlining.) Example:
February 1968 to September 1987: Junior Nosepicker
Hassis Toys, Old York City NJ
Selected probosci to include in "Mr. Tuberskull" toy kits. Supervised team of five Assistant Nosepickers. Invented five new styles of probosci, two styles of pimples, and new wart and mole add-ons. Saved 10% off departmental office supply budget, by implementing staple recycling program. Won "Employee of the Hour" award three times.
But what if you had several jobs at the same company? There are many ways to handle this. TO BE FILLED IN LATER!!!
Now, which jobs should you put on your resume? The advice on this varies quite a lot. Some guidelines (feel free to pick and choose which ones to obey):
Some people, however, say you should include all jobs you've ever held, but the ones that others would omit, these people shrink to a one-line summary. In such a summary, "shorthanding" the year is perfectly OK, as is leaving off the company location. Examples:
4/62 to 11/63: Street Sweeper, Old York Department of Transportation
1/55 to 8/61: Litter Picker Upper, Old York Park Authority
It might help if you can align them neatly, like this:
4/62 to 11/63: Street Sweeper Old York Department of Transportation 1/55 to 8/61: Litter Picker Upper Old York Park Authority
The "table" features of HTML and many word processing programs can help greatly with that.
If you called this something like Work History, and you have anything relevant to put in one, you can use an Other Experience section. That's where you put things you've done outside of work, that are still quite relevant to your job. For instance, if you're applying as tech support to an ISP, mention that you ran a BBS, or that you volunteered as your church's webmaster. The format should be roughly the same as the above.