I only use conditionor on the ends,and only shampoo my hair once.
I would use shampoo for greasy hair, but it washes the colour in my hair out.
I wash my hair every second day, as even though my hair looks rotten after the first say, I dont want to go down the road of washing it every day!
Any shampoos/conditionors that would help?
eh, wash your hair every day. If you don't have dry hair, you can't get away with it. Unwashed hair stinks (literally) and it's awful if someone sits beside you and you can smell greasy hair.
you need to use a clear shampoo - like VO5 or timotae. You mentioned your hair is coloured so I guess you're using a colour shampoo? They're about as bad as it gets for fine, greasy hair tbh. If you REALLY have to use it, ditch the conditioner altogether. edit: also, shampooing twice may wreck your colour but it does help for greasy hair
How you dry your hair is important too. Blow drying it properly will extend how long it looks clean for, because it lifts it off the scalp so the hair isn't sitting in skin oil the whole time. pull the top of your hair up into a clip and dry the under layer of hair with a hot brush, then let down the top layer and dry the top layer with a hot brush, always making sure to pull the hair up away from the scalp.
Also, this one isn't really all that great for your hair but I KNOW it works... Wash your hair as normal and then rinse it with salty water. It's not great for your hair because it dries it out, but if you really really really don't want to wash daily, you could maybe rinse your hair with saltwater at the end of the first day and let it dry naturally.
I have greasey hair too. Use a clear shampoo, not one that looks creamy. Like the other poster says, I use Herbal Essence. Wash it every day, blow dry it, and once I have that done, I never brush my hair again for the rest of the day. Mine is shoulder length and it doesn't need to be brushed constantly. I cut out conditioner altogether. For a night out, or a day out that I want my hair to really do it's best all day, I blow dry some volumising mousse into it. Just a small handful of it and spread it out evenly.