Old posts but it's worth having a good description to reference to. Kava is great but you have to prepare it properly and drink it the right way. It won't work right unless you do it just right. You need to get the best kind, noble kava. Get the kind they say is strong with mind and especially body effects. The stuff from Vanuatu is awesome. Fiji and a few other islands have the good stuff. Once you have the basics down you can experiment with other stuff.
Don't get the micronized or concentrates. You're better off getting the real stuff and doing it like the islanders. They've been drinking it for centuries and getting all fucked up. You need a powerful blender or mixer and a straining bag. You can buy one for cheap or an old t-shirt works fine. Mix the powder and water on medium high to HIGH on the blender or mixer for a long time. 5-10 minutes.
The longer you blend it at high settings the better it works. You want an emulsification, it causes the good stuff in the kava to get suspended in the liquid. Warmer temperatures, 75-110 degrees F work best. Don't go higher than 120 F, it'll kill the kava. Cold doesn't work as well. Then you strain it through your sieve bag or t-shirt or whatever you're using. Save the stuff you sieved, you can reblend it to get the rest of the stuff out of it.
The stuff doesn't taste good, no getting around that. Sometimes it'll make you nauseous but resist the urge to puke. Don't try mixing it with other shit, it just means more to drink. A lot of people try mixing it with dairy. That's a bad idea, don't do it. The best thing is to cool it off. I add a bunch of ice cubes and store it in the fridge. You want it cold but not so cold you can't chug it.
That's exactly what you want to do, chug it. Drink as much of it as fast as you can without puking. The other trick is to have an empty stomach. Any food will stop your stomach from absorbing it. Especially heavy food with fats and oils. Meat, dairy, bread and other starches aren't good. If you have to eat something fruit and melons are your best bet. Fruit juice will cut some of the nausea. If you drink the stuff on a full stomach you'll never get off.
How much should you drink? I'd say at least 32 oz at once. As much as you can get down and keep chugging. It's not easy but you'll be rewarded by a delightful body high and a solid head stoning. Walking becomes difficult. Don't try to drive. If you need to sober up a meal of heavy food will help. A light meal of fish or chicken and salad or a potato, or just fruit before bed will result in a good night's sleep.