Custom CSS not applied after changes

I have made changes to my custom CSS on the sharepoint portal using sharepoint designer. then I saved it. I went to check on the protal, however The changes I made were not applied. I check the CSS using chrome's developer tools and I was modifying the correct sheet but the changes I made were not included there. why sharepoint is not applying the changes I made to css? I checked in the css then checked it out but nothing seems to work. It is already published. I researched and found that I should clear BLOB cache? How do I do this exactly? but I'm afraid this may affect the server so I rather not do it since I'm new to sharepoint development. Why the changes are not applied? Is there any other way to fix it without clearing BLOB cache?