How can i make sand? and how to shrink the map?

For sand, what you’re going to want to look into are displacements- they’re a type of brush that let you deform certain surfaces of it. Here is a video on how they work-

View: https://youtu.be/04cVm3bwM3s


I recommend you don’t go above power 3, though. Power 4 has a lot of problems. And only create displacements on the surfaces you absolutely need, in your case, just the top.

As for water, all you need to do is make a brush out of the “nodraw” material, select the top surface, and turn that surface into a water material, which you can find by searching “water” in the materials browser. The volume of the brush will determine where you can swim. Keep in mind that you should keep all of the water on your map at only one level if you use an “Expensive” water material, which render reflections.

Hoovy Pooter™ said:

and also I made the map a little bit too big and I wanted to ask is there way on how to make it small?

Click to expand...

Unfortunately, there is no way to scale down your map properly, and while you could select all of your brushes and scale them down, this would move everything off-grid, making it a nightmare to try to work with. Sorry to say it, but if your map is overscaled, it's likely your best bet is to learn from your mistakes and start over.

Also a tip for getting your scale right, you can place a prop_static set to a player model to help give yourself a sense of scale
This also has the added bonus that the player models will not show up in game as they are not set up to work with prop_static