Narasimha JAyanthi is celebrated on Vaishakha Shukla Chaturdashi.

Lord Vishnu appeared in the form of Narasimha, a half lion and half man, to kill Demon Hiranyakashipu.

When Vaisakha Sukla Chaturdashi, Saturday, and Swati Nakshatra come together on the same day, it is considered as most auspicious

ಸತ್ಯಂ ವಿಧಾತುಂ ನಿಜಭೃತ್ಯಭಾಷಿತಂ ವ್ಯಾಪ್ತಿಂ ಚ ಭೂತೇಷ್ವಖಿಲೇಷು ಚಾತ್ಮನ: |
ಅದೃಷ್ಯತಾತ್ಯದ್ಭುತರೂಪಮುದ್ವಹನ್ ಸ್ತಂಭೇ ಸಭಾಯಾಂ ನ ಮೃಗಂ ನ ಮಾನುಷಂ||

Sathyam Vidhathum NijabruhthyabhashithamVyapthim Cha Bhoothaeshwaghileshu Chatmana|
Adhrushyatha Athyatbhutha RoopamudvahaN Sthambhe Sabhayaam Na Mrugam Na MaanushaM||

[Bhagavatha , Saptama Skanda , Adhyaya 8 , shloka 18]

Men should do Saligrama pooja followed by chanting of Narasimha sthothragalu, women can sing suladhi, Devara nama about NArasimha devaru

Click this link to Have wonderful darshan of Narasimha devaru: Narasimha Darshana

Ashtothra:

Lakshmi Narasimha Ashtothra Namavali

Sthothragalu

1. Sri Nrisimha Maha-mantra 
2. Prahlada virachita Narasimha sthothram
3. Narasimha Nakha stuthi(by Madhwacharyaru)
4. Narasimha sthuthi(Narayana pandithacharya virachita)
5. Sri Nrusimha Ashtakam(by Sri Vijayeendra theertharu)
6. Sri Narsimha Avatara stothram(by Sri Vadirajaru)
7. Narasimha Sthuthi by Sanaischara
8. Narasimha dwadasa Nama stotram
9. Narasimha Prapatti
10. Runa vimochana slokam

For women, Sing/Recite following:

• Dasara padagalu on Narasimha devaru
• Narasimha prathrurbhava(kannada) (Composer: Purandara Dasaru)
• Suladhi:

Apamrutyu Nivarana Suladi
Sri narasimha devara suladi(By Vijaya dasaru)
Narasimha suladhi by Jagannatha dasaru