1. University Rankings & DAAD website
The first step is to find all the relevant universities for your target course(s). Browse through the below university lists. These can be filtered based on a particular course/faculty/region etc.
Secondly, you can sort them according to their world rankings to get a sense of which university is better (although German education system does not claim any university to be better than the other). There is no official university ranking within Germany. However you can have a look at different ranking systems and come up with a sorted list.
2. TU vs. Fachhochschulen
Almost all the German universities for Higher Education fall under one of these two categories. Universities including Technische Universität (TU) and Universities of Applied Sciences or Fachhochschulen (FH).
are research-oriented and offer a wide variety of subjects. These can award doctorate degrees.
are practice-oriented and have strong links to the industry. These do not award doctorate degrees.
The distinction is quite clear. Here you can decide on which one of these categories suits you the best. It is also okay to be open to both the choices.
3. Intake and Course Requirements
A majority of universities have winter intake. But few courses only give admissions in summer. Again, filter based on this criterion. Winter intake will surely give you more choices than summer. However, if your favorite course is offered only in summer, do not hesitate to go for it.
Now with the remaining universities in the list, you can start having a look at their course requirements. If they have a threshold score or a mandatory requirement that you can not meet, you can cross off that university from the list. e.g. if you do not meet the entry criterion like GATE/GRE score card, IELTS 6.5 etc., your application will not pass through the first stage of the admission process.
4. Course curriculum
This is a mandatory step before you decide to apply for any university. Have a thorough look at their curriculum. See the type of courses, distribution of credits, other things like Internships and Master thesis need to be completed in order to get your final degree.
Make sure that the curriculum is aligned with your interests. Discard the ones which do not fit.
5. Other Influencing Factors
One of the most effective ways is to talk to your seniors (people who are currently studying in Germany) and inquire in our facebook and whatsapp groups. Lastly, you can consider these factors to arrive at the final list.
Remember that, in the end, the university is going to be the one choosing you. Do not go overboard with too much optimism. Make an informed decision based on your current credentials. I would suggest picking no more than 5-7 universities. Then you will have a better chance of focusing on these selected universities. Also, you would know the reasons why you want to apply to those universities.