Hoe do I show my condolences?

Flowers would be a great idea. Just tell her how you feel. At these times it is best to speak your mind. Maybe take something else with you (cookies?) or offer to make dinner for her (if you like to cook). Just let her know you are there.If she doesn't know of any way to help, ask her in a week. She's probably in too much "shock" (?) to think of anything now.