Update Readme.md

Readme.md

@@ -2,7 +2,16 @@
 * Ubuntu 16.04 LTS
 * ROS Kinetic
 * Gazebo 7.14 
-  * You can use this script [here](https://raw.githubusercontent.com/PX4/Devguide/master/build_scripts/ubuntu_sim_ros_gazebo.sh)
-  1. Download or save it somewhere
-  2. Go to the location that you saved it
-  3. source ubuntu_sim_ros_gazebo.sh
+  * You can use this script [here](https://raw.githubusercontent.com/PX4/Devguide/master/build_scripts/ubuntu_sim_ros_gazebo.sh):
+   1. Download or save it somewhere
+   2. Go to the location that you saved it
+   3. source ubuntu_sim_ros_gazebo.sh
+# OpenUAV #
+This simulation is based on [OpenUAV](https://github.com/Open-UAV) project.
+1. In your home directory create a `src` folder by typing `mkdir src` in your terminal
+2. `cd src`
+3. Clone all git repositories in OpenUAV to this folder by `git clone` command
+4. Go to the `Firmware` repository by typing `cd Firmware`
+5. `source setup-install.sh` (press <kbd>Return</kbd> to continue when asked)
+6. When it finishes, type `make posix_sitl_default`
+7. Then try to run Gazebo by typing `gazebo` in your terminal