How do I clean and what do I use to clean sink drains, gets smelly

I dump cloryx down mine but I am on city sewer. If you are talking about a sink or tub not used much, then the trap is drying out....just keep water in it now and then and the smell can't get up from the sewer.

baking soda followed by white vinegar,lemon juice, orange juice

i like to use baking soda and vinegar. Pour dry baking soda down drain first, then pour vinega, let’s it bubble away adding more of each until you’re satisfied with result. Then pour very hot water to finish it off. Very inexpensive and you can use old baking soda from fridge!

I have used white vinegar with good results,use 1 1/2 to 2 cups per drain ,just pour and let it sit for a while ,to deoderize a dispozer quarter a large lemon and grind it up and let sit for a few minutes before flushing .

Baking sofa and viniger

Or bleach