Plenty of methods. Stimulants are off the table for obvious reasons. Opiates/benzos/barbiturates (if you can source them, unlikely) would be the desired ones. Benzos on their own aren't going to do the job unless you take an ungodly amount; but opiates are a decent option. If you take pills (oxycodone/hydrocodone) they're likely to be mixed with APAP (acetaminophen). APAP will do nothing but cause severe liver damage and a very painful, slow death of jaundice and dialysis. Heroin, fentanyl/an analogue of fentanyl such as carfentanyl are your best bet. If you have pure heroin, and are opiate naïve (no tolerance to opiates), 600mg+ of heroin would be a reliable way to ctb. The issue comes in sourcing a pure product. Most of what you find on the street is going to be heavily stepped on. Finding a reputable Mexican source will be your best bet here; but you probably don't want to end up in prison, as it will make ctb much more difficult.
Best case scenario, you source some (mostly) pure heroin, and drift off into a blissful and euphoric eternal slumber. Make sure no one is going to find you for atleast 6 hours, as narcan will immediately reverse the effects and send you into precipitated withdrawals, potentially with brain damage, dependent on how long you were unconscious.
A lot of street opiates/opioids are either heroin cut with fentanyl, or fake pressed oxy's/hydros cut/entirely made of fentanyl.
If your an average sized 170 lb male, with no tolerance, 600 mg of pure heroin, 400 mg of oxy/ hydrocodone, or 3-4 mg of fentanyl would be enough to 100% induce a lethal OD. Ensure you don't take any stimulants (methamphetamine, adderall, vyvanse, cocaine, crack, ephedrine etc.) as these can keep you going even after large doses of a depressant.
I think the biggest reasons people on this forum don't go for opiate OD's is due to sources and the stigma surrounding it. People want some form of dignity when they go out, and "junkies" are usually wrote off as lost causes.
