The Tigers paid dear for errors as they slipped to their fourth straight defeat against Warrington Wolves last Saturday.
"You can see there's no lack of effort but we are shooting ourselves in the foot continuously," said head coach Matterson (pictured).
"We've got to learn our lessons. We haven't been doing and we'll pay the ultimate price this week if we don't fix those errors."
Castleford will be huge underdogs against a Saints side that thrashed them 66-28 at The Jungle in April.
But Matterson believes Castleford need to concentrate on their own performance rather than think about who they are playing.
"Who were are playing is not what we have to focus on. There are areas we need to get right and need to improve in," he said.
"We need to go over there and give a good performance to give ourselves a chance of winning the game regardless of who the oppposition is.
"The bounce of the ball is not going our way but there's two ways you can deal with this issue. You can feel sorry for yourself and keep your down down or you can get out there and work hard and try to fix the areas we are coming up short in. That's what we are doing. We worked really hard on Monday and had a good look at ourselves. We've got to bounce back.
"The results haven't been coming our way but we have been very close and that's what was disappointing last week. I felt that we could have put a score on Warrington and that showed at the start of the game.
"We conceded two tries to intercepts. We lost by 16 points and there's 12 of them and that's basically the difference in the game."
The Tigers will be without Michael Shenton and Joe Westerman who are on England duty in France but they will welcome back winger Michael Wainwright who missed the Warrington defeat after sustaining a head injury against Huddersfield the previous week.
Said Matterson: "We've got Michael Shenton and Joe Westerman out but St Helens are without probably two of their best players James Graham and James Roby so that probably more than squares things off.
"I may have to re-jig the side a little bit like I had to do last week. It's not ideal because you'd like to stay with your combinations. I will have a look what's best for us."
Matterson could switch Brett Ferres from the second-row to centre or he could bring in James Ford. He also has to decide whether to play Ryan McGoldrick at full-back or stand-off.
The Tigers are still without Ryan Hudson (broken arm) and Brent Sherwin (foot injury).
Matterson said: "Experience is costing us big time. Obviously we are without our captain Ryan Hudson and our half-back Brent Sherwin but that's a reality and we've given some good performances without those guys.
"Ryan is probably two or three weeks away. It's been slow healing and it's been frustrating but it's important that's it's properly healed. We can't muck around with these sort of things because if it's not fully healed and he goes out there there's a chance of it re-breaking."