...I washed it last on Saturday. (It's now Wednesday afternoon) My scalp feels slightly greasy due to sweat so I rinsed it but my hair is not greasy at all and is as it usually is. Do you think it'd be okay to wash my hair with shampoo now and get it coloured within 3-4 hrs from now?

I read online that washing hair right before with shampoo etc is a bad idea and that rinsing is alright considering the amount of days it hasn't been washed.

My hair has never been bleached before and is jet black. The hairdresser will probably be bleaching my hair but I'm not sure if the greasiness or dirt build up of the scalp would affect it.

Please advise. Thanks!