this is really important
yes, black, white, and grey hijab are essentials. they always match to every outfit you wear. you can combine them to with colourful hijabs or printed hijabs, anykind of hijab that you like. but having hijabs in every colour is not a mistake.
cardigans always help us hijabify any nice and cute outfit that needs covering. of course, black, white and grey are the neutral colors that match with other colors. but remember, cardigan is only for informal event or just hanging out.
you can wear blazers to formal event. match them with dresses or suits. recently you can wear blazer to informal events too. blazer + t-shirt + jeans = cool.
i prefer wearing long sleeve top as coverings.
hmm i think that's all i can say. i hope this will help you guys :)