How to sign: a wild and exciting undertaking (not necessarily lawful)
Similiar / Same: escapade, risky venture, dangerous undertaking
Categories: labor, project, task, undertaking
How to sign: take a risk in the hope of a favorable outcome
"When you buy these stocks you are gambling";
Similiar / Same: gamble, take chances, run a risk, take a chance, chance, risk, hazard
Categories: assay, attempt, essay, seek, try
Within this category: go for broke, luck it