действовать осторожно

1) General subject: act with caution, act with discretion, pussyfoot, take in a reef, tread lightly, tread on eggs, proceed cautiously, take in a reef, tread upon to tread lightly, watch steps, tread carefully (You should tread carefully when buying tires because the right choice can affect their performance and how long they last.), tread lightly (тактично), go undercover

2) Literal: feel one's way

3) Australian slang: play it cool

4) Diplomatic term: pull a punch

5) Politics: (to) tread the careful path

6) Jargon: take it slow

7) Makarov: feel way