The former Newcastle United youngster has penned a two-year deal in Paisley and has been joined in the Buddies' attacking arsenal by Englishman Sam Parkin.
After being released from his contract with MK Dons, the 26-year-old spent time in Scotland with Danny Lennon's squad in the second half of the season and Samson hopes familiarity will breed success for the Saints forward.
He said: "Lewis was in training with us a lot.
"It has been good for him that he has been able to come up. I think the manager would have liked to have signed him in January but because he had played for two clubs he wasn't able to do that."
He went on: "It is good that he has been able to come up and be around the team and he has fitted in with the boys right away.
"He looked really sharp in training and I am sure he will be raring to go when pre-season starts."
With Guy, Parkin and former Cowdenbeath midfielder Jon Robertson already tied up, Lennon has gone some way to putting his plans in place for the new campaign as the Buddies bid to improve on their eighth-place finish.
Lennon's side had set their sights on a top-six spot and while they ultimately fell short of breaking into the upper half of the table, the signs were encouraging for the Paisley crowd.
Going one step better next time out would be a significant achievement for the club but Samson is not getting ahead of himself.
He said: "We finished eighth this year and that was great for the club but we want to keep improving. The manager and Tommy Craig know how they want to play and they will keep their high standards next year.
"We have got to go and try and progress from last season and do the best we can. Getting into the top six would be great but I am not someone who sets targets. I would rather we just went out and tried to win as many games as we can and let the rest take care of itself."
Samson was an integral part of the Saints squad that achieved their highest league finish since returning to Scotland's top flight, with the keeper nailing down his place as Lennon's No.1 shot-stopper.
The 28-year-old has just a year left on his deal but is keen to extend his stay in Paisley if the club want to open contract talks.
He said: "There were a few boys out of contract and the manager was rightly looking to tie them down before thinking about other deals.
"If the club wanted to speak to me, I would be delighted to talk."




