Here's a little idea that I came up with, hope you'll find it enjoyable:
-Each week there'll be a new color or pattern and what you're going to do is to change the color of either an outfit, accessory etc.
-You can't use the same outfit, accessory etc that another user has used and you can only change the color of an outfit, accessory etc that doesn't have the specific color/pattern. If there's more than two colors for a theme one of the colors can be there if you want to
-After a week there will be a poll!
-Remember to not edit the outfit itself, just the color/pattern!
-And don't forget to have fun :)

Round 1-Red (29th May-5th June)
Winner: aurora2011
Round 2-Pink (5th-11th June)
Winner: dimitri-07
Round 3-Green (12th-18th June)
Winner: Awinitarose
Round 4 - Blue (19th-25th June)
Winner: BelleAnastasia
Round 5 - Purple (1st-7th July)
Winner: Awinitarose
Round 6 - Yellow (13th-27th July)
Winner: aurora2011
Round 7 - Brown (28th-3rd August)
Winner: aurora2011
Round 8 - Black (4th-10th August)
Winner: aurora2011
Round 9 - Grey (11th-17th August)
Winner: Tigressfan10689
Round 10 - Gold (18th-24th August)
Winner: LightningRed
Round 11 - Silver (2nd-8th September)
Winner: BelleAnastasia
Round 12 - Orange (9th-15th September)
Winner: BelleAnastasia
Round 13 - Flowers (17th-23rd September)
Winner: Jessikaroo (based on the comments since there was a tie breaker)
Round 14 - White (24th-30th September)
Winner: identity511
Round 15 - Hearts (1st-7th October)
Winner: SweetPea2007
Round 16 - Dots (8th-14th October)
Winner: identity511
Round 17 - Stripes (15th-21st October)
Winner: Jessikaroo
Round 18 - Multicolored (22nd-28th October)
Winner: BelleAnastasia (the poll was deleted, but this was the winner when I checked last time)
Round 19 - Pink and Purple (28th October-4th November)
Winner: hajirah4
Round 20 - Red and Blue (5th-11th November)
Winner: iHyrule
Round 21 - Yellow and Black (12th-18th November)
Winner: BelleAnastasia
Round 22 - Green and White (19th-25th November)
Winner: BelleAnastasia
Round 23 - Yellow and Orange (26th November-2nd December)
Winner: Jessikaroo
Round 24 - Gold and Silver (3rd-9th December)
Winner: BelleAnastasia
Round 25 - Red and Yellow (10th-16th December)
Winner: BelleAnastasia (she was the only one to submit for this round)
Round 26 - Pink and Green (17th-23rd December)
Winner: BelleAnastasia
Round 27 - Red and Green (24th-30th December)
Winner: aitypw
Round 28 - Sparkles (31st December 2012 - 6th January 2013)
Winner: BelleAnastasia
Round 29 - Red and Pink (7th-13th January)
Winner: BelleAnastasia
Round 30 - Blue and White (15th-21st January)
Winner: BelleAnastasia
Round 31 - Yellow and Green (22nd-28th January)
Winner: nmdis
Round 32 - Pink and Black (29th January-4th February)
Winner: nmdis
Round 33 - Pink and Blue (5th-11th February)
Winner:LightningRed
Round 34 - Any Romantic Color With Hearts (12th-18th February)
Winner: SweetPea2007
Round 35 - Any Of The Colors Of The Rainbow (19th-24th February)
Winner: Sirea
Round 36 - Any Color That Matches With The Princess Emotion In The Picture (25th February-3rd March)
Winner: No one
Round 37 - Any Color That Symbolizes Spring (6th-12th March)
Winner: iHyrule
Round 38 - Free Choice (13th-19th March)
Winner: Sirea
Round 39 - Red With A Pattern Of Your Own Choice (22nd-28th March)
Winner: dimitri_is_hot (she was the only one to submit)
Round 40 - Pink With A Pattern Of Your Own Choice (1st-6th April)