Meditate with high focus on good energy for about a half an hour, then stand up and stretch. You'll feel a rush of euphoria that will last at least 10 minutes. No matter your religion, I'm an atheist and it works.
Weed will do it. Try it.
JWH-018 and other synthetic cannabinoids are available all over the internet and they are still legal in many countries, they can be found in a "pot Puri blend" called spice or even bought in pure crystal form although this is VERY powerful, doses range from 2mg to get you high, anything over 50mg and youll start to hallucinate and all kinds of madness ensue
Codeine is easily available over the counter and is an opiate (it is metabolized by your liver into morphine) and can give you a very relaxed high, be warned of 2 things though, most OTC codeine pills contain large doses of aspirin or paracetamol so youll need to remove those before ingesting as the paracetamol will damage your liver, the other thing to be wary of is that its addictive stuff
Dextromethorphan or DXM is an active ingredient in many over the counter cough syrups such as Robitussin or benylin and is a powerful hallucinogen, at lower doses it will simply give you a light stoned feeling, at higher doses it will send you to other worlds. Again be careful of mixtures that contain paracetamol, aspirin or other dangerous substances, do your research before hand and be safe
Kratom is a herb which contains several opiates and is still legal in most counrys it can be smoked but is more regularly made into tea and drunk for a mellow high, you can get it online and at many head shops
there are plenty of other substances that can get you totally off your face and many are still perfectly legal, but always do your research first and be responsible and safe, you can find extensive info and user reports on those and many other substances at www.erowid.org