Don't listen to any of the stone age bullshit about putting belts or wallets in a person's mouth if they have a full blown, grand mall (tonic-clonic) seizure. You're endangering their life by doing that. They're NOT going to bite their tongue off, but they might choke on vomit if you stick something in their mouth. Possibly turn person on their side to keep airway clear and prevent choking if vomiting occurs. DON’T restrain movement. DON’T put anything in the person's mouth. There's no stopping the seizure it just has to run its course.
On the lines of the milder seizures, one kind that seems to have been described here used to be called Petit Mal, but is now more commonly known as Absence seizures. That's where a person kind of spaces off and just stops for a short period. I had these as a kid and never really knew they were happening. It was just like I wasn't there for a second or two and the world kind of skipped. The medication sucked but it did eventually help. Many kids have this form of epilepsy and it often disappears with puberty (like with me.) Some people may have minor muscle twitches to signal these episodes, while others will not. Again, this is a situation where the seizure just has to run its course. There's no talking someone out or waking them up. This is a neurological disorder not psychological.
A seizure is a change in sensation, awareness, or behavior brought about by a brief electrical disturbance in the brain. Seizures vary from a momentary disruption of the senses, to short periods of unconsciousness or staring spells, to convulsions. All seizures are caused by the same thing: a sudden change in how the cells of the brain send electrical signals to each other.
There are tons of resources for epilepsy on the web like:
www.epilepsyfoundation.org
E-community message board
www.epilepsy.com
A great deal of visual information and videos
www.cdc.gov/Epilepsy/