There are a lot of ways to learn and get a Certificate in SAP MM. But, first and foremost, I will suggest self-practice, and go through the syllabus and most importantly you can write an online practice exam which will give you confidence before attempting the actual exam.
And do check out the courses on SAP provided by Intellipaat to get an in-depth understanding of each and every important topics theoretically and practically:
Following tips will help you to get a better understanding and for certification:
First, try analyzing the syllabus, to get a fair understanding of the topics that are relevant to your certification. And then, you can find an overview of the related topics on the certification. And these will be more focused on the subjects which are weighted more heavily on the exam questions and hence will have more importance and worthwhile for studying.
Note that you are not advised to memorize the things, but, try to read to understand the concepts for sure. Because, in certification, SAP is examining to test your conceptual knowledge, but not your memory.
If you want to learn SAP MM from scratch, then here's the right video for you:
If you are more into reading, then do check out this material provided by Intellipaat:
To get a better grip on the topics, you will have to perform the exercises for all the topics with the system. You can also subscribe to premium practice tests for SAP MM Certification. These tests have questions close to the actual exams and an ambiance that makes you feel that you are giving the real exam. Attempting SAP MM practice tests time and again will help you to score better than every previous attempt. And, every attempt at SAP MM practice test will be learning for you. Try to score better every time. This would definitely lead you towards the desired target.