1. console your parents. don't control your emotions. if u want to cry, cry
2. get death cert from hospital and govt, and compare prices at funeral homes. Last time we went to a few to compare. It cost us around 30000+ that time and we did not book the largest hall at G/F. Some people only book a small room upstairs so it cost less. You can buy a lot of stuff from shops intead of the funeral home, like stationery for recording gifts, white clothes to wear.
3.book cremation(fire burial) date after confirming date with funeral home. If u burn the coffin, need not buy expensive one. 2-3K
4. get a list of friends and contacts and notify them to come to the furneral
5.prepare flowers, coins, sweets, tissue for 吉儀
6.超度:does your sis have a religion. For budism,超度 can cost 20k+ for a complete course at the funeral, and once each week for 7 weeks! for Christians, suicide is a crime, so no超度. U can ask the priest if he is willing to ask congregates to pray for your sis.
7.If she did not leave a will, u have to apply for probate to dispose of her assets. If she has a joint account, take the money from the bank first.
If u want to place her ashes in govt sites, there is a long queue. My 99 was in a Buddist Cemetry in Chai Wan and the urn spot cost around 6k, no waiting.