Be relaxed they want to see how bubbly and confident you are to speak to people face to face and on the phone.
Just go in like it was a normal interview smile look nice smell nice have good hygiene and be smart
Visit the shop - get to know the charity and what they do.
Be aware of the fashion trends
Its more about knowing you as a person so as long as you have a friendly nature and kind attitute you will be ok
You should prepare for an interview at cancer research by telling them why you want to work at cancer research and how you don't mind working extra days or hours (optional). you should dress smart or in casual wear for an interview .
Look into what the company does.
How the money they receive gets put into research