How many mushrooms do you think it would take a first timer to get a trip off of. My build is 6' 180lbs.
depends on the size of the shrooms. anywhere from one bite off a big cap to like 30 little mature shrooms. tough call, really. if it were me, i'd weigh out about 3.5g for your first time and call it a day. peace.
Split it if you mentally feel that you need to. Mentally, if you think that you can handle it, then you will be able to handle it. It really comes down to your mentality while tripping. Personaly, I would take the whole eigth.
an eighth is just 3.5g, which is a medium-strong dose according to erowid.org. personalyl i would never consider taking less than 3g, as i think it would be a waste. but i like to trip too, i don't like to just feel a little high. arguably, however, i should probably take more like 4-5g. i have friends who regularly eat around 15g dried; they say 5g is MINIMUM for a real "trip." i believe them, but i am not up to 5g yet. 4g is pretty rockin' though. anyway, for first timers i still hold to the 3.5g. my first time i ate closer to 4g and it felt like a couple hits of acid. it's amazing, just do it, you'll be fine. peace.
Your in washington state? what kind are they? 3grams can't be too much, but it could be too little, depending.
Species. If they're wild and local, they may be considerably stronger by weight than the p.cubensis standard. They may also be considerably smaller. So 3 g's is safe no matter how potent the species- but not enough to trip if it's p.cubensis.
eat half an eighth, then later on, once it hits you, if you feel you can take another half, take another half.