You may often need reindent your code. You can set F1 key to reindent your code by following steps:
Preference → Key Bindings → Add following code in the block
{ "keys": ["f1"], "command": "reindent" , "args": { "single_line": false } }
If you want CTRL+SHIFT+F instead of F1, just copy and paste following text
{ "keys": ["ctrl+shift+f"], "command": "reindent" , "args": { "single_line": false } }