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Don't trust people who praise you to your face.
Literal
Face-to-face you [object-を] praise-like [possessive-の] person [object-を] trust-[must-not-してはいけない].
Yet another rendering of the don't-trust-flatterers proverb, this time with explicit 'you' (あなたを) as the direct object of praising, and the deliberative negative obligation 信用してはいけない ('must not trust') instead of the bare imperative. ~てはいけない is the standard polite-ish 'must not' form.