All Android devices are not created the same. One method of rooting can support some of devices but not all devices. So there's no general process of rooting an Android device. But I will tell you how to get instructions to root your Android device.
1. You can join in a "Closed Group" on Facebook by searching it. Just Log in to your FB account and type on the Facebook Search bar the name of your device. Them look for Closed Group and join them. It will take upto 24 hours for you to be accepted, some groups takes less than an hour. After having accepted in the group. You may now check to their files regarding on how to root the device or just simply ask them how to.
2. Search Engines' power. If you can't wait for the Admin to accept you in the group, you can search it up to Google Search or other search engines. Just type "how to root + your Android device name." Then you will see lists of of websites having an article about rooting your device. Just remember to have time reading feedbacks and comments if their instructions are really working.
3. Video tutorials. If you want a video tutorial you can look up to Youtube videos showing how to root your Android device. Just don't forget to read comments if the process is working.
If the three ways given above weren't helpful, maybe I could help you. Just put your comment here including the name or model of your Android device. If you don't have enough knowledge about ROOT or Android rooting, you must read this - Advantage and Disadvantage of Rooting Your Device.