If mIRC is closed, then you can't.
However, if mIRC is minimized, then you can set it up in the Address Book (Alt + B)
Go to the Highlight tab
Check Enable Highlight
Click Add
Enter $me in the box under Highlight lines that contain these words.
Select Message or Both for the Match on dropbox.
Check Tip Message
Enter $1- in the box Message:
Click OK
Click OK

NOTE: I left the timing for the display of the tip at the default of 3 seconds. That can be changed to 60 seconds in the dropbox beside where you checked Tip Message.