My is question is: at which side (right or left)a woman have to sit to do pooja with her husband?
Women traditionally sit on the left side of their husband in a pooja (you can say the side of the heart, or if you would like another explanation on the left so that the right hand of the husband is ready for action). This is illustrated in the following shloka:
Dakshine Lakshamanoryasya, vame cha Janakatmaja,
prishthe Marutaryasya, tam vande Raghunandanam.
(On whose right is Lakshman, and on the left the daughter of King Janaka (Mother Sita),
in front is the son of Maruti (Hanumana), worship that scion of King Raghu's dynasty.
With best regards,