Hoping for help on signs and indications

My girlfriend is 24/7 care taker for her brother. He has epilepsy and is intellectually challenged. He has the wherewithal to mostly take care of his daily needs. He has a seizure every couple of months. Years ago they used to be multiple times per day. His medication (7 times a day) has reduced it to the current level however he sleeps 12-14 hours a day. When he has a seizure he just goes unconscious. He has been injured a number of times from the resulting fall. For him lack of sleep and stress and excitement seem to bring them on but not always.

The first thing I want to ask about is I understand that many people can feel a seizure coming on. He does not seem to. What do you feel or what are the signs? His sister can sometimes tell they are coming on. He talks to himself a lot and when that changes she is careful and will ask him to sit down. That way she can support him from injury. There are one or two other very subtle clues she can use but I can’t detect them.  Is there something we can teach him to look for so he can tell he is going to have one so he can make himself safer? What kind of indicators do other people get?

Thanks

Lee