Docs: Update README.md (#19456)

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devenv/README.md

@@ -1,37 +1,40 @@
-This folder contains useful scripts and configuration for...
+# Set up your development environment
 
-* Configuring dev data sources in Grafana
-* Configuring dev & test scenarios dashboards.
-* Creating docker-compose file with DBs and fake data.
+This folder contains useful scripts and configuration so you can:
 
+* Configure data sources in Grafana for development.
+* Configure dashboards for development and test scenarios.
+* Create docker-compose file with databases and fake data.
 
-# Dev dashboards and data sources
+## Install Docker
+
+Grafana uses [Docker](https://docker.com) to make the task of setting up databases a little easier. If you do not have it already, make sure you [install Docker](https://docs.docker.com/docker-for-mac/install/) before proceeding to the next step.
+
+## Developer dashboards and data sources
 
 ```bash
 ./setup.sh
 ```
 
-After restarting grafana server there should now be a number of data sources named `gdev-<type>` provisioned as well as
-a dashboard folder named `gdev dashboards`. This folder contains dashboard & panel features tests dashboards. 
-
-#### Dev dashboards
+After restarting the Grafana server, there should be a number of data sources named `gdev-<type>` provisioned as well as
+a dashboard folder named `gdev dashboards`. This folder contains dashboard and panel features tests dashboards. 
 
-Please update these dashboards or make new ones as new panels & dashboards features are developed or new bugs are
+Please update these dashboards or make new ones as new panels and dashboards features are developed or new bugs are
 found. The dashboards are located in the `devenv/dev-dashboards` folder. 
 
-# docker-compose with databases
+## docker-compose with databases
+
+This command creates a docker-compose file with specified databases configured and ready to run. Each database has
+a prepared image with some fake data ready to use. For available databases, see `docker/blocks` directory. Notice that
+for some databases there are multiple images, for example there is prometheus_mac specifically for Macs or different
+version.
 
 ```bash
 make devenv sources=influxdb,prometheus2,elastic5
 ```
 
-This command will create a docker compose file with specified databases configured and ready to run. Each database has
-a prepared image with some fake data ready to use. For available databases see `docker/blocks` directory. Mind that
-for some databases there are multiple images, for example there is prometheus_mac specifically for Macs or different
-version.
-
-Some of the blocks support dynamic change of the image version used in docker file. The signature looks like this - `make devenv sources=postgres,openldap name-of-block_version=9.2` -
+Some of the blocks support dynamic change of the image version used in the Docker file. The signature looks like this: 
 
 ```bash
 make devenv sources=postgres,openldap postgres_version=9.2
-```
+```