Before going for Kashi yatra (Varanasi):

Before going to KAshi Yatra,one needs to do Saikatha Pooja (Poja for Sand idols) at Rameshwaram.You need to split some handful of sand  into 3 parts as 

1)Sethu Madhava,
2)Veni Madhava and
3)Bindhu Madhava idols.

One must put Veni Madhava (sand) in Triveni sangama at Allahabad to make the yatra fruitful.Likewise  one has to bring Ganga Theertha from Kashi and do abhisheka for Sri  Ramanatha Swami to complete the yatra.