are you really going to start talking about "easily overdosed" when the drugs you're comparing it to are lsd (active in the microgram range) and mdma (active in the milligram range)?
seriously, you feel like you can get away with claiming that cannabis is more dangerous than a drug that most people encounter as mystery pills at a party? get real.
in legal states you can buy properly labeled edibles at a shop. if it's homemade stuff, you really have to be a lot more careful. either make it yourself or really trust your supplier. personally I would never take edibles bought from a dealer unlabeled. that's a real risk of an uncomfortable experience.
I think smoking (or vaping if you're sensitive to the smoke) is by far the safest and most effective way to take cannabis though.
LSD and MDMA there are really no safety tips that can possibly help. you either trust your source or you don't. if you trust your source and follow the dosage guidelines it's fine. both of those drugs are very safe at appropriate doses.
You CANNOT overdose on cannabis. As in it will not kill you.
The only way you could say that is if you have some weird definition where by having a "bad trip" counts as an overdose.
No matter how you spin this one, you have to be careful with whatever road you choose to go down.