After you rest in your dorm room, you can have picnics, where you can hang out with your Pokémon and become closer with them.
How to Unlock Picnics
Picnics are unlocked after you rest in your Dorm Room in the Academy. This will add the Picnic option to the X menu.
How to Have a Picnic
After you unlock Picnics, go outside to a place with level ground and choose Picnic from the X menu. You will automatically set a table, and your Pokémon will appear.
Picnics with Friends
You can open the Poké Portal option from the X Menu and choose Union Circle, then choose Form a Group to get a Link Code to create a group for friends, or choose Join a Group to use an existing Link Code to join an existing group. Then when you start a picnic, your friends in your group can join you.
Washing your Pokémon
You can press X while close to a Pokémon to wash it. Hold the A button and move the Left Stick to use soap on the Pokémon, then press Y to switch to the shower head. Hold the A button and move the Left Stick again to rinse off the soap. This will make your Pokémon clean, restore their HP, and increase your friendship with them.
You can press A while facing a Pokémon to talk to them.
Press R to whistle, which will make your Pokémon come toward you.
Recall or Bring Out Koraidon/Miraidon
You can press the + button to bring out or recall Koraidon/Miraidon.
Throw a Ball
You can press ZR to throw a ball, which your Pokémon can kick back to you. You can also walk toward the ball to kick it.
Redecorate the Picnic Table
You can check on the picnic table to redecorate it, changing the tablecloth, water bottle, and cup.
Choose a Ball
You can check on the picnic table to choose a ball. This will change which ball you throw if you press ZR.
You can also use picnics to breed pokémon. If any of the Pokémon in your party are compatible with each other for breeding, you can periodically check the basket on the ground next to the picnic table to see if there is a Pokémon Egg inside. If you have Egg Power active from a meal or sandwich that you have eaten (press (right on the directional pad) to check), it will take a shorter amount of time before an egg appears.
During a picnic, check on the picnic table and you can choose to make a sandwich. You can either use Recipe Mode to make a sandwich from a recipe that you already know, or you can press X to switch to Creative Mode, where you get to choose up to 6 fillings, then press the + button and you can choose up to 4 condiments, then press the + button to select a pick. Press A to start prepping the sandwich.
While prepping the sandwich, the condiments are placed on the bread automatically, and then you have 10 minutes to place the fillings. Press A and use the Left Stick to pick up each of the fillings and drop them onto the bread. After you have placed the fillings, you can place the top piece of bread, and then put the pick into the sandwich.
If you are playing in a group with other players via the Union Circle feature of the Poké Portal in the menu, you can make sandwiches together. The bread will be bigger, making it easier to add more fillings.
Get More Sandwich Recipes
After you get Gym Badges, Titan Badges, or Star Badges, visit any location of Every Wich Way and talk to the person in front of the counter to learn new sandwich recipes.
Get More Sandwich Ingredients
Visit the different locations of Artisan Bakery, Deli Cioso, and Sure Cans throughout Paldea to purchase more sandwich ingredients. There is also Acquiesta Supermarket in northern Levincia, which is the only source of Tofu, Wasabi, Horseradish, Curry Powder, and Klawf Sticks. In addition, certain ingredients are only available from 5-Star or higher Tera Raids, which are unlocked after you have seen the end credits.
Pack Up and Go
When you are done picnicking, you can either press Y to pack up and go, or you can check on the picnic table and choose Pack Up and Go. Your pokémon may gain experience points afterward. They will gain more experience if you wash them during the picnic.