、。
Moderate exercise in the evening helps you sleep.
Literal
Evening [at-に] moderate exercise [object-を] do-[conditional-と], sleep [object-を] induce-[nominal-のに] be-useful.
Two grammar points worth noting. The ~と conditional again marks a natural consequence: 'when you exercise moderately, it helps.' Then 誘うのに is the nominalizer の plus the target-of-purpose に — 'for the purpose of inducing [sleep].' 役立つ ('to be useful, be of help') takes this のに-marked purpose. Compact written advice.