No need to worry. Inspect the engine for external oil leaks such as various failing/leaking gaskets and replace them. Then switch to a better oil brand like Shell, Liqui Moly, Mobil 1, etc. Also, some oil consumption is considered normal as per owner's manual for some cars because of the extreme pressure and heat inside the engine. So if you've done all of the above and notice oil level declining slightly after a few months without blue smoke then don't worry. It's all normal.
