Comment on Market Watch & Trading Screen
There is an option of scripted alerts where you can set price alerts. Open the scripted alerts window, select the contract, and then set the alert.
For example fore reliance
Buy:
Set A = 900
Close>900
Sell:
Set A = 850
Close<850
Take this alert live, whenever this happens you get a beep sound, and also the alert gets logged in the generated alerts window. You can also do this using Expert advisors, check this post.