MacBook Air Storage - Deleting 'Other' items

I have been sitting and watching my overall Storage reduce by 0.02GB every 30 seconds or so and my 'Other' storage increase by the same amount. I now have 50.21GB out of 121GB in my 'Other' storage.

How do I access and remove whatever is eating my storage or is it another Apple ploy to get me to buy iCloud storage space?