Jags fans got their first chance to see Alan Archibald's side in action this summer when they were held to a 1-1 draw by Championship outfit Dumbarton at the Bet Butler Stadium on Saturday.
Ryan Stevenson's first goal for the club spared Thistle's blushes after Bryan Prunty headed the Sons in front.
It was far from the kind of free-flowing and accomplished performance Thistle turned out regularly last season but Craigen is certain he and his team-mates will be more than ready for their first league match at home to Ross County on August 13.
The midfielder said: "You can't really put a number on how many games you need to be ready but we will be raring to go against County, just like we were last season against Dundee United.
"Going into the Premiership last year we didn't really know what to expect but we certainly know what it will be about this time round.
"A lot of the players hadn't played at that level before but we have a year's experience there now and know what will be waiting for us."
Craigen felt the weekend match was another valuable stepping stone towards the new season for Thistle.
He said: "It is always a good test coming to Dumbarton and it was a worthwhile game.
"At this stage of the season it is all about fitness and sharpness. I thought it was a good exercise for us.
"We pressed well and the lads got more playing time under their belts.
"I feel I am getting there now. I have played a few 90 minutes and a couple of halfgames, so I'm feeling good."
Next up for Thistle is a trip to Belfast on Sunday to face Glentoran before they travel to Fleetwood then host Sunderland.
Craigen is confident the Jags will be in perfect shape for the visit of County after that run of games.
He said: "The preparations have been fairly similar to last year. The trip to Spain was great, the facilities there were excellent and we were looked after really well.
"We have the same ethos as before. We are working hard and looking forward to the start of the season.
"There are some good tests coming up for us as we build our fitness and sharpness. We will all be ready for that first game of the league season."
With just a couple of weeks until the opener the clock is ticking for manager Archibald to add numbers to his Firhill squad.
On Saturday he cast his eye over six trialists, with Darren Barr, Jordan Mustoe, Hamza Bencharif, Kalen Damessi and Matt Parsons being given a chance to impress.
Craigen said: "The manager is looking to strengthen the squad and that can only be a positive thing.
"We still have the core from last season and there could be another four or five coming in.
"We'll have a strong squad and hopefully we can go out and do the business again.
"We still want to go and play our football. There will be tough games but we know how to cope with those now."