Well I just did a quick search and found some books. So I got some other questions. Right now my Bonsai is in my backyard is just below 60 degrees F. It suppose to rain tomorrow and when it does, should I bring my bonsai back in or not?

What are humidity trays? I was looking around the new and found humidity trays.

I have found the best book for beginners is BONSAI put out by Sunset Publications. It covers a lot of information, and should be one of the first books in any bonsai growers library.

Your tree can take the cold down to 20 F., which should be just fine where you live, and if it snows, let it. If it rains, however, as your tree is probably not in a good bonsai mix (they never are!) it may stay soaked for way too long, so do keep it somewhere it won't get wet (til you decide to water). What you need to do (spring will be ok) is get rid of most of the peaty soil it's probably in (and if there's a layer of pebbles glued to the top pry it off and discard it), and make up a mix of a little coarse soil, a good handful of small aquarium gravel, pine bark bits 1/8-1/4", and perlite - if you have trouble finding the bark (must be clean - forest stuff will have bug eggs, etc.) then use a good packaged orchid mix - the idea being that a mix like this will drain fast. And water only when ~ half of it is dry. Humidity trays aren't needed for junipers, but can be set up with those big wide drip/drain trays sold for large container pots with sides of 1-2" high. Fill it with stones and water... but the water never quite as high as the stones, so your pot on the stones won't attract water back inside and rot the roots.

I started bonsai about a year and a half ago and this book was and still is my bible.
The Bonsai Handbook
By David Prescott & Colin Lewis
Give you every thing you will need to know to get going. He gets deatailed enough that I had success on my first layer!