in my experience, 200 seeds was more than enough. I'm sure 300 or 400 wouldn't be too bad though, as supposedly different seeds affect different people in various intensities. Also, unless you have some weed on had to handle the nausea, don't just grind them and eat them. If you have time to prepare, grind the seeds, dissolve the powder in water and then filter it with a coffee filter. Throw out the filter and solids, and evaporate the water on a cookie sheet (with a fan). You'll be left with a brownish sludge which you then re-dissolve in as high % alcohol you can get (everclear works great, but if you can't get that the just look for the best % vodka or rum). Drink the alcohol and you're set. Don't forget to let it sit in your mouth for a second or two, because it's the mucus membranes that actually absorb it, not your stomach. This will provide the best, most clean and visual trip, while allowing you to control the dose (as it should hit you immediately). If you don't have the time/supplies then just chew the seeds (they taste like dust and rocks) and swallow them. This reduces the nausea and keeps the 'headache factor' form being as pronounced as it would be if you just ate the ground powder, as it is contained in the husks which you probably can't chew well enough. Last thing, don;t freak out if you get vasoconstriction or a heavy heartbeat, it's normal and healthy. If you're just eating them it should hit you in about 3 hours, peak at ~5 hours, and then slowly wear down until you don;t notice anything roughly 8-12 hours after ingestion. protip-dose in the morning, they're called morning glories for a reason.