Yes I would suggest snips or clippers with a sharp edge as I can see you splitting the bamboo using scissors.
There are alot of handy tools such as 'dremel' which offer you lots of interchangerable parts these will cut through bamboo well.
A sharp stanley knife will work well too as long as you have a protected surface to cut on and with all the above ideas a good straight line to follow.
The main problem I have had with bamboo blinds is mould due to window condensation - when it gets started it will spread quite fast leaving green blinds and a mouldy smell. I dont know if varnish or some sort of mould resistant product would prevent this but I think that if these blinds are expensive or cover a large area it might be a good idea before you hang them to treat them for mould.