Dear Student,
The best way to identify the reaction mechanism is to know that what type of reaction requires which types of condition and what are the products formed if that mechanism is followed. For eg. if a tertiary haloalkane is subjected to hydrolysis by a weak nucleophile to form alcohol, then definately SN1 reaction is followed since tertiary haloalkanes give SN1 reaction readily. Moreover, presence of weak nucleophile is also an indication of SN1 reaction.