If you've been reading my site for a while, you know that I don't agree that pages should look the same in all browsers. I believe that designers who focus on this tend to think of Web pages like print media and so want them to look the same no matter who looks at them. But first and foremost, you should consider good design practices.
However, since so many designers want to create pages that look the same in most browsers, I felt like I should give you some hints on how to do it. One of the first things you should do to make your pages look the same across browsers is to get rid of the default styles. I do this with a master style sheet. This is similar to my CSS cheat sheet I gave you a few months ago, but it's more specific to clearing out the default styles in most browsers. Note, this is different from a "global reset" because it doesn't turn off styles that would be destroyed if they were removed (ie. if you remove native styles from form buttons, you can't put them back).
Worthy post intresting read.