1 . Make sure to uncheck all "DLCs" for Dota 2 in your Library.

Optional, but recommended: re-install Dota 2 after 1st step

2 . Use the 32 bit version ( put -32bit in launch options )

3 . Check Dota 2 cpu core affinity ( Run Dota 2 , open taskmanager, go todetails, rightclick dota2.exe, click affinity, set to all cores )

4 . Use high process priority ( put -high in launch options )

5 . Try out different directx versions ( -dx9 or -dx11 in launch options ) or OpenGL if you use an nvidia GPU ( re-tick OpenGL support DLC and -gl in start options )

6 . Set up your graphics settings to your likings

7 . Play Dota 2