Optimization?

[stormtrooper106]

So my first map it looking nearing completion....However, my map now starts to lag when ever I load it up. Though, it is not a bad lag, but it looks a little choppy, like the framerate had dropped a little. Now, before you say anything about graphics cards, and computer specs, that's not the problem. I can run Amnesia and other games perfectly fine on ultra settings. So, I'm pretty sure it's because of the lack of optimizing my map.... And I looked around on the wiki, and I didn't find any topics about optimizing maps......unless I missed it or read over it.....tends to happen when you have ADHD, and it makes your attention span rather small, and takes your concentra..."OOOH LOOK AT THE SHINY THING ACROSS THE ROOM" *Looks at shiny thing* XD
But, my question is, what are some methods of optimizing maps if there are any?