There have been a lot of talk here these last years about SN and there's some stuff that seems to be a general rule to make it work fast and with little discomfort and mess
1: Search for a tranquil place were you know no one will find you (or hear you) for at least 12 hours after you use it
2: Fasting at least 8 hours before taking sn
3: Use SN of at least 99% purity
4: Use the correct dosage (25 gr in a 50 ml glass aprox), have at hand at least 2 glasses in case you vomit
5: Drink the sn and lay in a comfortable chair or bed
6: be sure to be convinced that you really want to ctb
There's people who will talk about taking anticids or other drugs, but I dont think that its neccesary, In fact I think that could make your stomach worse and prompt vomiting