There has always been a major confusion for new learners of Spanish over the translation of the English, to be. This is because, Spanish has two different words (estar & ser) for this verb and you need to be extremely careful in their usage. Any mistake might drastically change the meaning!
That said and done, it is very tedious to learn the complicated rules on where to use estar and where to use ser. This is where mnemonics come into play. Here's the mnemonic that I used while learning Spanish. It's called Doctor Elf:
Doctor (usage for ser)
D escription (Ella es alta.)
O ccupation (Soy profesor.)
C haracteristic (El es antipático.)
T ime / Date (Son las ocho; hoy es el ocho de julio.)
O rigin (Soy de Virginia.)
R elationship (Ella es mi madre.)
Elf (usage for estar)
E motion (Estoy contento.)
L ocation (Estoy al concierto.)
F eeling (Estoy enojado.)
Another way to remember the places where estar is used, is by memorizing the following rhyme:
How you feel and where you are,
That is when you use estar.
Think you'll ever make a mistake with these two Spanish verbs in the future? I don't think so. Happy learning...