I personally feel that all days are good for wearing Rudraksha. Shiva is one God who teaches us to be Free of all dogmas and traditions..by Himself roaming among the Bhutas and Pisachas with skulls and snake adorning Him. He is worshipped in the night with Shivaratri being His night. He is worshipped by householders and Brahmacharis alike and Himself was a householder yet the highest ascetic. His both children were not entirely born out of wedlock. He fought with His own Son (Ganesha) and killed His own father-in-law when His spouse ended life. He is the most passionate Lover as Kamastutra was woven around Him and at the same time the biggest renunciate with Shivasutras woven around Him.
While certain rules in religion are meant to bring some routine and order to our worship, true spirituality is expansive and limitless like the Universe in all aspects.