Hi, I'm new here. I see warm up excercises on the first 4 lessons so far... Do I keep adding them up to my everyday warm ups or each new one kills the previous?

Good question, Luis! You can use the warmup from day 2 as your daily go-to warmup (or download a full warmup for your voice type here: http://30daysinger.com/audio/bonus-warmups/Vocal%20Warmup%20Bonus%20Gifts.zip). 

The new exercises you learn will help you learn new skills and techniques - and you're welcome to incorporate them into your daily routine! But it may be simpler to just have a regular warmup, and then approach each lesson video as a standalone lesson to learn about a new element of vocal technique.