Cushion covers

When we painted this furniture a long (long) time ago our plan was to quickly find a gray fabric to make cushion covers. Plain gray fabric was harder to find than we thought. I think it took us a year and a half to find fabric we were happy with.

Here is what the chairs look like – you can see on one we found a fabric that we thought we liked but it turned out to be almost identical to the wall colour so we decided not to use it.

Here is the fabric we found. I’m sure we could have found something better but after looking for over a year we decided to just buy it. 

Now we just need to motivate ourselves to sew 8 cushion covers….

Does anyone know of a good tutorial for making cushion covers? We weren't too happy with the sample grey one we made (the one in the photo). We want to avoid zippers and tried using snaps but I'm sure we could do something better... Any advice is much appreciated!