I took my 10 month old on a 5 hour flight by myself last year and had a bassinet and eisle seat (a must). I found though that she was way too interested in everything else going on around her.

I took my baby bjorn (even though she was too big to carry for a long time in it) and This is the only way I got her to go to sleep. Walking in the small space near the toilets, up and down, up and down, until she was finally asleep, and I could sit down with her to continue her sleep.

Only other advice - be prepared and organised and use the flight attendents as much as possible (to assist - most are great)