Years ago (2012) I wrote a tutorial on installing Blender and setting up for making clothes in Second Life ™. It is titled: Second Life Mesh Clothes Blender 2.6 Setup 2012 Tutorial. It has all the gory details a person with OCD would need. A couple of years later I wrote: Fitted Mesh Base Avatar Files, about which mesh models to use for making clothes. The articles have good information but we have learned and advanced since then. So, we can simplify things.
This article will hopefully take some of the pain out of your entry into clothes making for Second Life.
Blender Install
There are two ways to install Blender™. You can install it as one does any Windows program using the provided install program. This is simple and quick. If you are just curious and in the process of exploring, this is your option.
However, if you are serious and committed to making clothes then there is a better option.
Blender is in what I consider rapid development and updates often. Some of the updates make changes in the core parts of Blender. These changes force third-party add-on makers to update their add-ons. If you are dependent on an add-on you’ll run into times when a Blender update will break your model and/or your add-ons and you are left waiting for a third-party update.