To invite the power of these deities during specific nights, one of the best things to do is to meditate upon their name. On Mahashivratri, think about Lord Shiva, his ascetic nature, him being the ‘Adiyogi’ and meditate upon his name. Chant his name, chant the Mahamrityunjay mantra, listen to the Shiv Tandav Stotram, or the Lingashtakam, and surround yourself with Lord Shiva’s energy.
On the nights of Janmashtami and Diwali, chant the name of Shri Krishna or Maa Lakshmi, and pray to them to give you all that you deserve. Ask Shri Krishna for wisdom and for love, and ask Maa Lakshmi for wealth, abundance, and peace.
During Navratri, pray to Maa Durga to protect you from harm, chant mantras, and ask her for forgiveness for any wrongs and ills.