When you go to light that bowl and its already finished, yet some ashy remains are still there, but you light it anyhow without knowing and you take a hit that tastes like pure ass crack.
When I smoked cigs - I could tell I was really stoned by how many I had going at the same time, 1 in ashtray, 1 in hand, lighting a fresh one...
Now I know if I forget to keep puffing a joint or bowl - just come to, and realize I've been sitting there for who knows how long w/ a batch sitting waiting...
Or I forget whose turn it is - did I just puff, or should I hit before passing???
You know you are stoned when you realize you have half a joint stuck to your lower lip, you have a pile of ashes on your stomach and you've been staring at a TV that isn't even on for the past hour.
When someone asks for your phone number, and you give them the first 3 digits before realizing you don't remember the whole thing. When you take out your phone to look up your own number, and you realize you can't remember the password to unlock the phone.