'Side started the brighter, but almost fell behind when goalkeepee Charlie Howson's clearance struck Newbury forward Reece Okugbeni, with the ball narrowly going wide.
Joe Oates enjoyed a fine spell for 'Side in the second-half of last season. The winger was arguably the hosts best player in tbe first-half, forcing Forest keeper Jordan Stansbury into two smart saves.
Elsewhere for 'Side Archie Hammond saw a shot blocked, whilst fellow midfielder Francesco Balestrini saw a curled effort go wide. Olajide Yusuff had the final chance of the half, but the forward shot into the side-netting as the teams went ibto half-time level.
Kieran Huddart flashed a volley wide fir Newbury at the start of the second-half. That was as good as it got fir Newbury, as to the delight of new biss Steven Le Sage, the hosts would take full control of the match.
Oates would pick up a cross from the right, scoring with a neat finish to put 'Side ahead on 51 minutes. Keeper Stansbury did get a glove to it, but couldn't deny the winger much to the delight of the home fans.
Twelve minutes later, it was 2-0 as Dan Jones scored on the rebound, from close range, after Stansbury had parried a drive from Oates.
'Side were wanting more goals and on 70 minutes wrapped up the points when Oates grabbed his second of the night, finishing well after a nice run.
With the game sealed, Le Sage made changes with Muyiwa Osenie and Ali Rajim coming on. The former made it 4-0, scoring on 75 minutes, two minutes after coming on. The forward pouncing on a poor clearance by Stansbury, to seal a fine win for the Sky Blues.
In the closing stages keeper Howson ensured a clean sheet for his defence, with a good save to deny Zacharias Panagiotou from grabbing a consolation fir Newbury.
Overall a great way for 'Side to start the season, with a great crowd of 145 present to see it. The Sky Blues are next in action on Sunday in the Extra Preliminary Round on Sunday 11th August, when they host Stansted (Essex Senior League) at home. Kick-off for that match is at 2pm.
'Side return to league action on Friday 16th August, when they host Hackney Wick at Cricklefields. Kick-off for that match is at 7:45pm.
'Side: Charlie Howson, Nathan Saunders, Shaquel Foyewa (Ben Clarke), Berkcan Belindir, James O'Brien, Elliot Scott, Francesco Balestrini (Ali Rajim), Archie Hammond, Olajide Yusuff (Muyiwa Osenie), Dan Jones, Joe Oates
Subs Not Used: Josh Hayward, Jude Fudge