I cranked out my exam with about 3 weeks study time. 2-3 hours a day for the first week, a 5 day span of no studying, then a week of 4-5 hours a day before taking the exam. I did have previous experience with a lot of it through college and work though. I used the practice exam textbook here as well as the study guide here to research my weak topics. I also bought Jason Dion's 6 pack of practice exams on udemy 2 days before my exam to confirm I was ready and I scored an overall average of 83 across all 6 tests on the first go around. Exam score was an 826 so I'd say put in a decent amount of time with the books until you feel comfortable and then take Dion's exams blind and see if you can score an average of 78 or higher. If so you're probably ready at that point. Make sure you're learning the material and not just the questions though, data dumping is only good once you have a decent understanding of the material.
Sorry for the late reply! Here is the link to my original post, then my thoughts on the book, then the link to the book. Let me know of anything else!
"Finally, I used Security+ Practice Exams third edition by Lachance and Clarke. I cannot stress this enough, this is a GREAT representation of the exam questions, 95-100% as difficult as the actual exam. The wording was spot on with the exam, there are in-depth explanations for the answer choices, and 19 exams with another exam and more questions on the CD that comes with it. ... (10/10) CompTIA Security+ Certification Practice Exams, Third Edition (Exam SY0-501) by Daniel Lachance and Glen Clarke: https://www.amazon.com/CompTIA-Security-Certification-Practice-SY0-501/dp/1260026906"