Your first step would be to acquire the proper packaging, which would include a new box with at least 3/4" insulation.
This time of year, there are definite weather and temperature concerns, and we cover that on the site. Phoenix in particular today is 108F(!) and that makes it very difficult to ship in or out of. Much of the rest of the country is just fine temperature wise, but it is an important factor to consider : )
Doing your first live shipment can seem daunting, but it is actually a simple and reliable process. The site will walk you through the proper steps, but you can also contact us directly and we will do it with you first hand.