I used gmpublish.exe it should be somewhere in the Garrys Mod directory, or you could just type out a .bat file with the line -

"C:\Program Files (x86)\Steam\steamapps\common\GarrysMod\bin\gmpublish.exe" create -addon "%~dpn1.gma" -icon "%~dpn1.jpg"
pause

Save it as something like gmpublish_create.bat

obviously with the corresponding file directory. If this isn't enough here's a link to a publishing guide > https://wiki.facepunch.com/gmod/Workshop_Addon_Creation

hey quick question what did you use to upload this

Just what I need.

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=479523226&searchtext=abandoned
very similar map to yours.

I like this map

I'll use this for my Porn sfm's Thanks!

Really Good map keep it up! Would like to see more maps/ updates from you!