I usually have them all done on separate days, usually colour then a week later Brazilian keratin then a week later cut. My hairdresser is way until next week so I can't ask her but is it possible / advisable to do them all on same day or if 2 on one day then 1 on a later day - which?
Can depend on the keratin brand - some can be done straight after colour. Would be a very long appointment!
Personally I get colour and cut done together and then my keratin treatment 2-3 weeks later. I normally have all over colour but sometime a few highlights in the summer. Definitely make sure I have highlights before the keratin is due to be redone as other way round meant the keratin didn't last as well as normal.