Quite simple. Make the post to establish the timestamp, then check to see the seconds time of your post is. Then, edit your post to state what you got and your reaction.
Oh, and don't take the "spend the day" part too literally.
00 - Watching movies together
01 - Playing hide-and-seek
02 - Beating up the avatar
03 - Getting beaten up by the avatar
04 - Pranking neighbors
05 - Hugging
06 - Sailing the seas
07 - Eating sandwiches
08 - Playing chess
09 - Committing arson
10 - Golfing
11 - Clothes shopping
12 - Playing Minecraft
13 - Strip poker
14 - Handcuffed together
15 - Shoving the avatar into a meat grinder
16 - Drinking beer
17 - Being sick with the flu
18 - Snowball fight
19 - Stealing cars
20 - Solving mysteries
21 - Having tea
22 - Locked in jail
23 - Playing baseball
24 - Having a rap battle
25 - Going to the aquarium
26 - Skydiving
27 - Being the campaign manager for the avatar's political career
28 - Being stuck in a broken elevator
29 - Crossdressing
30 - Making out
31 - Being each other's wingmate on a double date
32 - Swallowed by a whale
33 - Fencing
34 - Going to a basketball game
35 - Running a lemonade stand
36 - Playing on a beach
37 - Trick-or-treating
38 - Drag racing
39 - Sleeping together (literal, nonsexual sense)
40 - Having a really nasty argument
41 - Babysitting a child
42 - Time travelled to the past
43 - Time travelled to the future
44 - Married for a day
45 - Running away from Godzilla
46 - Screwing in a lightbulb
47 - Falling into a ravine
48 - Lost in outer space
49 - Swimming in a pool
50 - Freaky Friday Flipped
51 - Reverted to 4 years old
52 - Having a romantic spaghetti dinner
53 - Attending a Broadway production
54 - Fighting crime with superpowers
55 - Dealing with poison ivy
56 - Eating pizza
57 - Playing video games
58 - Showering together
59 - Breaking into a bank
I got 32, so I'd spend the day with the above theoretical avatar swallowed by a whale. Yuck.
Edited by Parable on Aug 10th 2023 at 7:25:08 AM
Christmas tree!
The tree has no arms.
Edited by Heyitsgalaxycreeper on Dec 4th 2019 at 9:25:12 AM
Ruler of Everything
With Freckle & Ivy
This seems fun!
Edited by TabbyGirl4 on Dec 4th 2019 at 1:28:11 PM
"I'm Mary Poppins, Y'all!" - Yondu,2017
Showtime!
With Moonlight Cookie
Sleeping together (literally). Hope she doesn't snore
Edited by Libraryseraph on Dec 4th 2019 at 4:29:54 AM
Absolute destiny... apeachalypse?
Kirby
With them.
What.
Edited by Oggy123 on Dec 11th 2019 at 11:14:24 PM
This is not a Rickroll, i promise
AKMU
With Lotte?
well that's good...
Edited by VXXXN on Dec 12th 2019 at 12:16:31 AM
da gloop go off? i yoink it and my splurg go off
With Rarijack
Uh oh.
Edited by MememasterFlex on Dec 15th 2019 at 12:36:22 PM
With angry cat person (IDK their name)...
Well, shit.
![[down]](https://static.tvtropes.org/pmwiki/pub/smiles/arrow_down.png "[down]"){kind=icon}
Yeah.
Edited by GoldenCityBird on Dec 21st 2019 at 6:18:43 PM
TRS Wick Cleaning
Nidokings and Nidoqueens
With Rosie (that's her name, right?)
Well, this is going to be a strange day...
Edited by kablammin45 on Dec 21st 2019 at 10:01:53 AM
"Wonder if Lexie's gonna be free after his shift today..."
With a legged Christmas tree, oh god why.
Please kill me in cold blood.
You probably don't want to know. Also you're under arrest now.
Edited by unfortunatezorua on Jan 6th 2020 at 8:16:09 PM
Well, that’d be jus’ a waste. Why would ya want to deprive the world of such anomaly as yourself?
Kirby
With Gon (?)
What does strip poker even mean?
Edited by Oggy123 on Jan 6th 2020 at 6:27:46 PM
This is not a Rickroll, i promise
Fits in Heavy's pocket!
Oh geez.
Well, it could've been much worse.
Edited by Murataku on Jan 7th 2020 at 4:25:16 AM
The last thing you hear before an unstoppable juggernaut bisects you with a minigun.
Dagded Dujardin
Me and the time agents, Cavendish and Dakota, will...
Well, this certainly is a funny episode of Milo's Murphy Law. Not because of me, of course
Edited by VengefulBale on Jan 6th 2020 at 11:30:14 AM
"Bingo! If two species hate each other, they will wipe each other out on their own."
AKMU
me and lord nightmare
fencing? im very likely gonna lose (and probably suffer from nightmares forever)
Edited by VXXXN on Jan 7th 2020 at 1:34:39 AM
Kirby
With Elena and Naomi.
But why?
Edited by Oggy123 on Jan 7th 2020 at 4:29:35 PM
This is not a Rickroll, i promise
Light and Hope
Squidward? Really?
Could have been much worse, I guess.
Edited by dave_the_assassin on Jan 7th 2020 at 6:01:32 PM
Hope: "Let's go. We'll be together." Lightning: "I only know... that soon, we'll be together."
Fits in Heavy's pocket!
Me and that tiny kid, probably that famous alchemist's bother or something.
Heh, he looks about the right age. 
Edited by Murataku on Jan 7th 2020 at 10:42:54 PM
The last thing you hear before an unstoppable juggernaut bisects you with a minigun.
Nidokings and Nidoqueens
Dakota, Cavendash, and me...
Vote to save the pistachios!
Edited by kablammin45 on Jan 7th 2020 at 11:05:37 AM
"Wonder if Lexie's gonna be free after his shift today..."
Light and Hope
Wrong thread; this is YOU and the above avatar.
Me and Ira.
.... IDK, I'm not very good at writing lyrics.
Edited by dave_the_assassin on Jan 7th 2020 at 10:59:13 PM
Hope: "Let's go. We'll be together." Lightning: "I only know... that soon, we'll be together."
da gloop go off? i yoink it and my splurg go off
Ed and I
Oh... oh my...
Edited by MememasterFlex on Jan 7th 2020 at 2:01:00 PM
CAC, my ASAS and HGS Author Avatar
Zatanna, right?
Perfect
Edited by CosmosAndChaos on Jan 8th 2020 at 6:15:56 PM
CAC: The other heroes are right. I can't give up!
Nidokings and Nidoqueens
With Serge...
That's more along the lines of Chrono Trigger, isn't it?
Edited by kablammin45 on Jan 8th 2020 at 3:05:43 PM
"Wonder if Lexie's gonna be free after his shift today..."
With Ira
Getting out probably won't take long.
Edited by unfortunatezorua on Jan 8th 2020 at 10:18:23 PM
Well, that’d be jus’ a waste. Why would ya want to deprive the world of such anomaly as yourself?
Kirby
With... whoever that is.
I don't really golf.
Edited by Oggy123 on Jan 10th 2020 at 12:58:36 AM
This is not a Rickroll, i promise
With a sentient Smash invitation...
Okay, A. that's just plumb awkward and B. wouldn't the water hurt the invitation?
Edited by kablammin45 on Dec 4th 2019 at 12:16:03 PM
"Wonder if Lexie's gonna be free after his shift today..."