In Little Misfortune, you will meet some choices while playing. Some of them have achievements tied to them, and here I will explain when and where to make a manual save so you can get both achievements in one run.

Early in the game, after you leave Misfortune's room, she will trip and make a vase fall over. Make a save here. You will then have the option of fixing the vase or leaving it be. Fix the vase, and unlock The Cause. Reload your save, leave the vase, and near the end of the game you will trip over the vase's ruins, unlocking The Effect.

After you exit your house and cross the road you will stumble upon a puppy tied to a tree. You must choose to set it free. Don't forget to pet the puppy at least 3 times to unlock the Lil' Cutie achievement.

The puppy will follow you to a beach, and it will dig on the sand to reveal a jar. Make a save here. When you click on the jar, you will have to choose between a fortune cookie and a dog treat. Pick one, then reload your save and pick the other one. Neither has long-term effects on your game.

After George's house, you will enter a cave, and see 2 hamsters fighting in front of a club. Make a save before you approach them. You will have the option to end the violence between them, or not.
If you choose Yes, Misfortune will separate the hamsters, and the one with the purse will run away. Further down the path you'll meet a pissed off old lady hamster. Behind her is a red button you must press to proceed. You'll enter a drug lab. Use your slingshot to hit the fire alarm, giving you the Sniper achievement.
If you choose No, one hamster will kill the other and drop the purse. Pick it up, return it to the old lady hamster, and she will give you a ticket to the club. Your chosen toy will have a dance minigame inside the club. Finish this minigame, and unlock the Dance Master achievement.
Feel free to do one path and then reload your save and do the other path.

At one point you will walk on a bridge and stumble upon a fish out of water. Bring the fish with you. Misfortune will name him Rodrigo. Later you will be in a park and see a sad seagull sitting on the sandbox. Make a save here.
Give him the fish, and he will eat it and spit back Rodrigo's bones. Then, proceed to the next area, the pet cemetery, and find an empty grave to bury his bones. You will get the Rotten Fish achievement.
Reload your save, and don't give Rodrigo to the seagull. Continue playing until you're on a boat ride after the carnival. There will be an option to use Rodrigo as bait to lure the Kraken. Use him, and you'll get The Kraken achievement.

At the zoo, you will come to a part where you must sneak through a crow-headed janitor. While this stealth section is quite easy, it's better to make a save just in case. If you managed to sneak pass her, you will get the Ninja Lady achievement.

You will later arrive at the aforementioned carnival, Phantasmagoria. Here, you will be given one ticket, yet for this achievement you need to ride the 2 rides. Proceed left to the next area with the Carousel and Haunted House, and make a save there.
Then, you have to ride one attraction, reload your save, and ride the other one. You will get The Returner achievement. I have read other guides mentioned that to get this you will also have to ride the Horse and Twister at the park, after the seagull. While I don't think this is the case, it's better to ride them too, and riding the Twister 3 times will get you the Too Much Rolling achievement.

So yeah, that's all the save/reload points you will have to do to get all the choice-related achievements. I hope this guide can help you during your playthrough. I would like to thank Neoneria's guide for helping me during my playthrough, and providing many great screenshots of the important moments. And of course, a great thank you to Killmonday Games for making this amazing game. Play their previous game Fran Bow if you haven't, and keep an eye out for their future projects!