From a Windows machine:

• XMing is probably the best way to go.

From a Linux machine:

• ssh -Y -C  [remote server address]
• [Login with username and password]
• [run an X program.  It will appear on your local screen]

 

Some report that using a different encryption is faster:

• ssh -Y -C -c blowfish-cbc  [remote server address]

-Y = enable trusted X-forwarding  (as opposed to regular -X)

-C = enable compression

 -c blowfish-cbc = use blowfish encryption (instead default of AES cipher, which is slower)

 

These methods can be slow when connecting over the internet (as opposed to over a LAN).   "VNC over SSH" may be faster.