1. First, insert parentheses around every occurrence of & and its two conjuncts, starting with the rightmost & and ending with the leftmost,
2. Next, insert parentheses in the same fashion for each ∨ and its two disjuncts, from rightmost occurrence first, to the leftmost occurrence last,
3. Finally, insert parentheses for each →, and its antecedent and consequent, from rightmost occurrence first, to the leftmost occurrence last,
As you follow this procedure, keep in mind that parentheses are never inserted around negations, and that a single parenthesis should never be inserted within another set, i.e., do not break up any existing pairs of parentheses with ones you insert.