Handle slightly separating from door...

Recently, I've noticed that when I pull up on the handle to open my door, the door handle assembly (or bezel ? ) pulls away from the door. Other than that, the handle works just fine. What do I do about this?
(forgive the bird poop in the pic)

 

Pull the door card off. You'll see some black plastic plugs in the sheet metal of the door. They look like stars sorta. Pull those our, and you can tighten the 10 mm bolts that hold on your handle.

I'll see if I can find pictures. Hang tight. Been a while since I've done this personally.

 

I don't have any pictures that I can find, but I do have a link to when I did it two years ago.
https://www.tundras.com/threads/tundra2s-lifetime-project.65626/page-2#post-1814974

 

How difficult is this? Not something I've ever done before.

 

It is not that difficult but it helps knowing some of the finer points. The below video is a 04 Sequoia but is same for my 04 Tundra. It should be same or close to same for your 06. While there are plenty utubes available, most don't actually show the finer points. This guy did a good job and should get you going. If you don't have plastic trim tools it's fine, just be cautious. It's not a bull in china closet project.
Caution also with inside door handle if yours is like that. The little 1/4" by 1/4" plastic cover over the screw can be fragile in taking off.

His total project is his door latch mechanism but you should only need the first 10 min of video for your project.