Here I've collected a few neat-o things you can do to customize TF 1.5. Yes, probably all of this information can be found in other locations. I've simply tried to gather some information together here to make it easier to share. Some of these tutorials build on each other. Go in order if you've got the time, definitely read about making a custom HUD before moving on to crosshairs and other sprites.
The examples created in the tutorials are available for download, with the exception of the Scoreboard/VGUI textschemes (there are too many resolutions for me to go through). Alternatively, all of the files can be grabbed as a .pak file, as described in the tutorial about Pak files and hierarchy. I also don't get into the editing of animated sprites, such as rocket glow, etc. RPG sprites are out there for the taking, and most of the other animated sprites you should leave well enough alone.
Have fun funking up your game.
Scoreboard and Commandmenu Appearance
If you get tired of looking at the same yellow VGUI "commandmenu" - then you're in luck.
Fortunately the good folks at Valve made it pretty easy to modify these menus, so you can play with
style.
Editing Titles.txt
Ever wished that the message flashed right in the center of your screen when enemies use your dispenser? Ever wished that you had a nice, colored message saying "OMG KILL KILL KILL" when enemies took your flag? All this, and more, can be yours with the help of titles.txt.
Custom Console Fonts
It didn't take too long for high-res players to realize that sometimes even the largest default font is barely
legible. So don't miss out on the important communications ("A/S/L") and also spruce up your own
font for a personal flavor.
How to Make a Custom HUD
Your HUD, or "heads-up display," is that area at the bottom of your screen that tells you how you're doing in
the health, armor, ammo, and gren departments. TF uses the traditional Half-Life HUD, which can get a little
old. We offer an excellent TF-Themed replacment, and instructions on how to make your own, of course.
Custom Crosshairs and Other Sprites
No point in sprucing up your HUD, Titles, Command Menu, and Fonts if you don't give Crosshairs and other
sprites the old spit and polish.
Pak Files and Hierarchy
The best way to organize all your custom sprite, model, and sound files.