Clark, who spent the second half of last season with Bostik League Premier Division Worthing, cited work commitments as the reason behind his switch to Steyning.
It is a major coup for Town head coach Gerry Murphy and he believes forward Charlie Romain’s friendship with Clark played a crucial part in him agreeing on a move to The Shooting Field.
Murphy said: “Louis is a great signing for us and he is a close friend of Charlie’s.
“He wants to play regular football and not be under the pressure of having to train twice a week, which is something he won’t get here.
“Danny Gainsford has also come back to the club over the summer and appears to be enjoying himself. We’ve recruited well over the summer and things are looking good so far.”
Steyning get their season under way in the FA Cup on Saturday – which will be a first appearance in the competition in 12 years.
Town travel to division-higher SCFL Premier Division rivals Worthing United for an extra-preliminary round clash.
Steyning then begin their SCFL Division 1 campaign a week later with Ringmer the visitors to The Shooting Field.
Head coach Murphy guided Town to a sixth-placed finish last season but he wants to see an improvement on that this season.
Murphy said: “The aim is to finish higher than we did in the league.
“We entertain Ringmer in our first league game, which I’m sure will be a tough test.
“We’ll be wanting to get off to a good start but I’m sure they’ll be looking to do the same as well.”
Steyning had a big squad last term, using 47 players over the course of the season.
Murphy felt a lack of consistency in regards to the playing squad may have had an effect at times in the previous campaign.
He said: “Something that may have accounted for some poor performances was a lack of consistency at times last season.
“I think we used something like 47 players in various competitions, which may have been too many.
“I’ll be looking for more continuity in terms of the playing squad this season.”
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