A year ago, Jackson opted to sign experienced campaigners such as Kevin Gall, David Graham and Stefan Oakes but the decisions backfired as the Imps fell short of the play-off places.
As a result, Jackson is targeting younger players this pre-season and signalled his intentions by signing 20-year-old Rotherham striker Jamie Clarke on Wednesday.
"This signing is a sign of things to come," he told the Lincolnshire Echo. "Last year we brought in older, established players like David Graham, but this summer we're looking at younger players.
"I'm talking to two players in their early twenties and am hopeful we can sort something out with at least one of them by the weekend."
Former Nottingham Forest defender Hamza Bencherif is believed to be on Jackson's radar as he looks to bolster a squad weakened significantly last month when he released eight players.