1. Dopamine.

Listen to upbeat music.
Get good rest.
Eat a sweet treat like dark chocolate.
Complete a small daily task.

2. Serotonin

Walking.
Going out to get some sunshine.
Meditation.
Cardio exercises.

3. Oxytocin

Hugging someone.
Cook a meal for a person you care about.
Talking with peers.
Petting cows.

4. Endorphins

Watching some comedy.
Burning essential oils.
Doing cardio.
Eating sweet treats like chocolate.