This solution is only for live FXCM accounts.
Before you can connect to FXCM through TradingView, you must first send a request to api@fxcm.com. Once you have done this, you can gain access via your token.
By visiting this link, you can see the same information provided in the Token Management tab on your broker platform. To find this tab, go into your profile settings and you should see Token Management above the Logout and Change Password tabs.