Usually it is best to be all in on one method, doing the best method available to you the best that they can. WHen peopel have plans for more than one method they often taken little short cuts on each method, thinking the other method will get me if thisa one doesn't- if they follow through like this, and take even one shortcut on each method then the odds of either one work8ng go way down. So normally I would say using one method is best. WIth those two methods, though, they could actually work together, and iuf you did them each without shortcuts it could improve your chances. Sn sometimes is very7 peaceful and sometimes is quite violent, there is a variation- Sn is still the best available method to me so it is what I plan to use. But is I had a good way to do CO I would do that instead, not in combination. It just depends on the details though- what is you plan for co? If you plan this in a public place you could get caught and stopped. If yo9u plan this in a closed garage and neighbors live nearby, it mnight be possible that they would call police about this, or even someone driving by might call the police. If you live in a remote location where and do CO in a garage this should be effective. If you live in a house by yourself and you try Sn withn a good plan it will likely work, and if it doesn't you will likely be very sick for a few days. If you live in an apartment or condo or try a hotel- vomiti9ng can be loud for Sn and someone could call for help. So much depends on the details on the plans.