I passed 640-801 with the score of 910 today!!! This was my second attempt. I failed my first attempt with 770.
I was sloppy studying on and off for this exam for about a year and finally I nailed it down!
I would like to take this opportunity to thank the following people:
1.
networker050184 who advised me not to rush to retake the exam after I failed my first attempt.
2.
barbatuses who advised me not to let the time control me during exam.
3.
NeonNoodle who showed me how to count the broadcast domains and collision domains.
Also thanks to those who read and answered my posts

The reasons I failed my first attempt:
1. I was nervous, panic, and over-confident.
2. I was not familiar with the format of the exam and I ended up answering ONLY 1 question of a 5-question Simlet.
3. I was worried about running out of time and rushed to answer all the questions. As a result, I messed up the Sim question.
4. I configure Cisco routers day in and day out but have very limited hands-on and knowledge on switches.
After I failed my first attempt, I was down for 2 days (the entire weekend) and quickly regrouped myself and became more committed to it. From then on, I studied at least 3 hours per day during weekdays and 8-10 hours during weekends. Of course, this forum has been accompanying me since then.
I already had my rewards in September in which I went to Maui for my vacation and today I went to OktoberFest

As for what's next, I am planning to get a taste of Juniper certifications and might eventually go for CCNP.
Cheers!