First of all, he needs to contact each pension scheme and find out what entitlements, if any, has accrued. Depending on the length of time he was in each job, he may be entitled to nothing, a refund of his contributions, a deferred pension on retirement (probably very small depending on length of service) or to transfer the funds into a PRSA or a buy-out bond.
Having found this out, he could contact a pension adviser (independant, of course) and go through the various options available and choose the same best suited to his needs.