When I do go out grocery shopping, I take precautions:
1 Wipe the trolley handle down with an antiseptic wipe
2 Wear a face mask
3 Take hand gel and use it frequently. Particularly after returning the trolley before driving home.
4 Wash my hands after unpacking
5 Try to put any new purchases at the back of the cupboard, for rotation purposes.
The virus can survive for some time on certain surfaces, which influences all of my actions except #2.
Since I don't have a stock of fresh face masks, mine gets sprayed with alcohol and left to dry in the sun or in a warm place after use.