Spread the cheesecloth over a large bowl. Stir the salt into the container of yogurt and after it is well combined, pour the entire contents of yogurt into the cheesecloth. Pull up the cheesecloth and tie the top-knot with string, leaving a long length to tie over the sink or overhead hook to drain.
Put a dish under the hanging cheese to catch the drips of whey that drains off and leave it to drain for at least 18 hours. The longer it drains the firmer the cheese will be.
Stir in oil and serve with your choice of fresh herbs.