Shields are halfway into their BetVictor Northern Premier Division campaign heading into tomorrow's game against Mickleover Sports at Mariners Park.
Joint manager Picton believes that the Mariners - who are top of the table and three points clear of second-placed Lancaster City, who have played three games more - can at least match their points tally of 45 in the second half of the campaign.
If they do that, he knows they will be tough to catch.
Picton said: "This is the first game of the second half of our league campaign and it's important we keep our standards high.
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"We amassed 45 points from the first 21 games and I firmly believe that if we can match or better that points haul we will be extremely difficult to surpass.
"To get three points on the board tomorrow would be a great start for us."
Mickleover are dangerous opponents for Shields, having won their last three games in the league to climb to 10th.
The Mariners go into the game with some serious selection dilemmas, with Blair Adams, Josh Gillies and Dillon Morse all now back in contention, along with recent signings Callum Ross, Wouter Verstraaten and Sefton Gonzales.
These are headaches Picton more than welcomes, though.
He added: "We're going to have to make some really tough choices on team and squad selection.
"The return of the likes of Dillon Morse, Josh Gillies and Blair Adams, plus the additions of Callum Ross, Wouter Verstraaten and Sefton Gonzales, undoubtedly gives us a completely different look to our squad compared to previous weeks.
"It's a dilemma we've craved but one thing is for sure, nobody's place in our team - or squad for that matter - is guaranteed with such high competition for places.
"Hopefully that will bring out the absolute best in our players and help drive consistently high levels of performance, which is obviously what we require in order to finish where we want to at the end of the season."
Shields will be without Luke Daly tomorrow after he was forced off in Wednesday's Durham Challenge Cup win over Billingham Town with a knee injury.
It was Daly's comeback match from a five-month lay-off from a previous knee injury, but Shields do not yet know how long he will be on the sidelines this time.
The Mariners will also be without goalkeeper Ross Coombe tomorrow.
Kick-off is at 3pm and admission prices - which can be paid at the turnstiles - are £10 for adults, £8 for over-65s and £3 for under-16s.
Students can enter for the discounted price of £5 if they show their student ID at the turnstiles, and will also receive a voucher for a free pie.
Season ticket holders, meanwhile, can claim a voucher for a free pint of draught lager, cider, craft ale or a soft drink if they enter Mariners Park before 1.30pm.