The clue is “Message to go in the Times (5)”
Please supply answers with explanations and what indicators you used in the clue. Thanks
The answer is:
TWEET = message (on Twitter). The wordplay is WEE, "to go" (to the lavatory) in T + T, "times" (t denotes time in physics ).
This clue is from yesterday's Guardian cryptic by Puck. The site I linked to provides detailed solutions for cryptic crosswords in the Guardian, Financial Times and the Independent.