Step 1: Open Up Steam
Step 2: Enter Your Settings
If you want to make a counterstrike source map, use the ep1 engine and choose the game counterstrike source.
For me, I'm going to use the ep2 engine.
When your done choosing the settings, doubleclick "Hammer Editor" at the top.
Step 3: Click on the Brush Tool
To start making the base of the map, click the brush tool. This is the small square icon in middle left.
Step 4: Click and Drag a Box
Once you press enter, press Control+H. A window should pop up. In the input, put in "-12" (negative 12). Then press enter.
Step 5: Apply Entities
Go back to one on the windows and click and drag to set yur camera. If you did that correctly, you should be looking at the inside of your box that you made at the top left window. You can now move around.
Once you get use to the controls for the camera, go down to the bottom of the inside of the map, right around the middle. We are now going to make a spawn point. In the toolbox on the left, click on the entities tool (the light bulb). Even though the default entity is the spawn point, I still want to let you recognise what do later on when you want to spawn things like nps, specicfic lights, ect. Click on the ground to make a spawn point. Your map is now playbale.
Step 6: Compile the Map
Step 7: Find Your Map in the Folder Destination.
If you want to move the map around to another folder (such as the gmod map folder), you can go to the link and copy and paste it to another folder. In a half life game, to run the map, open console and type in "Map (Exact name of map)". If you did it correctly, you should load into your map.
Congradulations! You made you first map! If you have any questions, just send me a message.