As some people will already know, when you sing and you say the 'esss' sound, you are blowing a concentrated amount of air into the microphone causing the sound to distort.
The best way to get rid of this is by using a plugin for your DAW by the name of 'SPITFISH', it is by far the best plugin i have used. Search for it on Google, download it and install it onto your DAW.
When you have it installed and have added to the track you wanted to use it on, all you need to do is make sure that the knobs are are both at the 12 o clock position. Also, if you have recorded the vocals in stereo, you will have to make sure that the 'stereo' option has been ticked.
Hope this has helped those suffering with this problem