Spent weeks reading through Salesforce OmniStudio official documentation and their guided experiences guides before my first attempt. Thought I had everything covered but the exam questions were completely different from what I studied.
Got frustrated and switched to itexamstopics.com exam topic-wise questions instead. Doing real practice tests made everything click way faster than reading those docs ever did. Two weeks of grinding through their practice exams and I passed on the second try. If you're going for OMS-435, forget the Salesforce docs and jump straight into practice questions. Their questions are solid and way more effective.