In this guide, when you are evolving, evolve as soon as you have enough DNA points.
Main Game--->Official Scenarios--->Santa's Little Helper
ATP Boost
(Empty)
(Empty)
(Empty)
Stmpto-Statis
It is important you leave the three gene slots empty--this will raise your overall score at the end.
Casual Difficulty
Start in China
Immediately evolve the symptoms:
Santa's Little Neurax Worm
Festive Tendrils
And the Transmission:
Emotive Radar
After this, wait for more DNA points, then evolve the following in the specified order.
Evolve the following transmissions:
Radio Worm
Memory Lane
Evolve the following symptoms:
Digital Elf
Digital Herald
Digital Angel
Laughter
Excitement
Joy
And evolve the following Abilities:
Surprise Delivery
Surprise Delivery
Surprise Delivery
Surprise Delivery
Then return to the transmissions page, and evolve:
Stocking Filler
Gold Digger
Then return to the abilities page and evolve:
Gift Plane
Present Parachute
Chimney Shoot
Red-Suited Pilot
Whenever you get a gift plane, press "Y", and look at the "Key Research Contributors" near the right side of the screen. Send the plane to the top research contributor.
Now evolve the following transmissions:
Snowballs 1
Solar Perfume 1 and 2
Glow Worms
Wild Side
Move over to symptoms and evolve
Contentedness
Appreciation
Harmony
Friendship
Affection
Love
Indulgence
Partying
Intoxication
***Note, if Sloth mutates, devolve it right away
Now just wait until the entire world is infected with happiness and cross your fingers! Good luck!
My final score was 85,476.