^^ agreed. except for the closing thing. i personally don't close mine, because the point was to open them. you can close them a little. i visualize round pearls in the light [and same colour] as whatever chakra it is, being polished and getting brighter. when i'm done [i'm a dragon practitioner so i normally see a dwarf dragon while meditating] a dragon comes by and takes the pearls, but the light remains.
at first, it's hard because there's so much gunk on each pearl that it takes a while to polish [plus myself in my meditations, when i try and grab something, they'll either move slightly out of reach or spin like crazy] eventually things will be bright blue, or red, or whatever colour. it just takes practice. sometimes i feel dizy while meditating, little things like that may happen to you, but like visualization, everyone's different, so you're experience may be different.
myself, when my chakra's are open [depending on which one] i'll feel more spiritual, or i can see aura's easier, or i can sense when a customer's behind me at work. things like that. research each one, then spend one day each day specifically on one chakra. the next week, try opening them all in one meditation. this will not only show you what each one opening will feel like, but it's help you learn each chakra, and how to open them.