Check there's oil in it, hook up a starter booster pack or new battery, turn the key wait for the pump to prime, if it doesn't you need to take a look at the pump and it's circuit, if it does, some choke, hit the starter. You're be amazed, I've started many bikes that were just like yours, my own Fazer once stood for about 5 years, it just started second prod.
If it runs, it's possible it my not run on all cylinders straight away or not at all, if that's the case you will need to whip the carbs off and clean out the pilot and possibly the main jets. Many will tell you the fuel will have gone off etc, in my experience it doesn't make that much difference, obviously that depends on the tank cap sealing and there being no water ingress.
Worse case drain and refill, while your there doing that, check the tank for rust, generally they're sound, providing it's not been damaged (sharp denting) that cracks/peels off the inner coating. The same with plugs and caps, if the bike was good before taken off the road, been under cover, with reasonable ventilation, it should all work, that said you made need a squirt of WD.