How do I know when to use 'ser' and when to use 'estar' if they both mean 'to be' in English?

This is a really common struggle for people learning and studying Spanish, even at university level. It's understandable because when we want to translate 'to be', for example; I am Naomi, I am friendly, I am in England, I am happy, etc. In English we obviously would use the same verb in all of these situations but in Spanish you would either use 'ser' or 'estar', depending on the situation and the context. In general, the verb 'ser' is used to refer to things that are either permanent or lasting. You can use the acronym DOCTOR to remember in what situations you would usually use this verb: Descriptions (soy Naomi), Occupations (somos estudiante), Characteristics (son amables), Time (es la una), Origin (soy de Inglaterra), Relationships (ella es mi amiga). The verb 'estar' on the other hand is used to refer to more temporary situations and the acronym LoCo can help you remember when to use it. It stands for Locations and Conditions, so Locations would be 'Estoy de pie', 'Está a la derecha', 'Está allí', etc. Conditions would refer to temporary states, ie. how someone is or what they are doing in that moment, e.g. 'Estoy feliz', 'Está preocupado', 'Estoy trabajando'.