Update presets.md

docs/presets.md

@@ -1,16 +1,16 @@
 # Presets
 
-imgproxy preset is a named set of processing options. Presets can be used in [URLs](generating_the_url.md#preset) to make them shorter and somewhat readable.
+An imgproxy preset is a named set of processing options. Presets can be used in [URLs](generating_the_url.md#preset) to make shorter and more human-readable.
 
 ## Presets definition
 
-The preset definition looks like this:
+A preset definition looks like this:
 
 ```
 %preset_name=%processing_options
 ```
 
-Processing options should be defined in the same way as you define them in the [URLs](generating_the_url.md#processing-options). For example, here is a preset named `awesome` that sets the resizing type to `fill` and resulting format to `jpg`:
+Processing options should be defined in the same way they are defined in [URLs](generating_the_url.md#processing-options). For example, here's a preset named `awesome` that sets the resizing type to `fill` and the resulting format to `jpg`:
 
 ```
 awesome=resizing_type:fill/format:jpg
@@ -20,11 +20,11 @@ Read how to specify your presets with imgproxy in the [Configuration](configurat
 
 ## Default preset
 
-A preset named `default` will be applied to each image. Useful in case you want your default processing options to be different from the imgproxy default ones.
+A preset named `default` will be applied to each image. This is useful when you want your default processing options to be different from the default imgproxy options.
 
 ## Only presets
 
-Setting `IMGPROXY_ONLY_PRESETS` as `true` switches imgproxy into "presets-only mode". In this mode imgproxy accepts presets list as processing options just like you'd specify them for the `preset` option:
+Setting `IMGPROXY_ONLY_PRESETS` to `true` switches imgproxy into "presets-only mode". In this mode, imgproxy accepts a presets list as processing options just like you'd specify them for the `preset` option:
 
 ```
 http://imgproxy.example.com/unsafe/thumbnail:blurry:watermarked/plain/http://example.com/images/curiosity.jpg@png