Getting Started with Git
Once you've installed git, get acquainted with some of the concepts through this series of guides from Atlassian:
Other suggested guides:
The Basics: http://rogerdudler.github.io/git-guide/
Full guide: http://git-scm.com/book
A git workflow model: http://nvie.com/posts/a-successful-git-branching-model/
Getting Started with GitHub
2. Create a GitHub account at http://www.github.com
Follow these steps to configure an SSH key for your account. While not required, this makes commits easier.
Optional: Using a Git GUI
A number of GUIs exist for Git which take away some of the guesswork involved in running from the command line. Git actually installs with one. On windows, it can be found in the start menu ("Git Gui"). You may also see it called gitk on the web. However, this gui is very minimal. Developers would benefit from installing an additional GUI.
If developing in text-based languages, Visual Studio Express 2013 provides direct integration with Git through an embedded version of the tool (ie it does not require the separate command line download).
3. Install SourceTree (Recommended)
If developing in LabVIEW, a separate tool is currently required. In the past, TortoiseGit and GitExtensions were recommended for LabVIEW development. At time of writing, the best tool seems to be SourceTree, which has a very modern visual interface as well as integration with Git and Mercurial as well as GitHub, Bitbucket, and Stash.
Recently, a user on LAVA posted a new project integration tool for git. It may suit your needs:
Optional: Set Up Diff and Merge
The LabVIEW diff and merge tools included in the professional version are described in the following help topics:
Git is a very Linux-centric tool and it provides all diff and merge paths in linux notation (that is, /c/file/path/here). It also assumes that most will be done using the command line interface, so everything is provided as a relative path to the working directory (pwd). This causes a number of issues, which are exacerbated by the merge tool's reliance on GUI interactions. If a merge was unsuccessful, there is no way for git to know if it was successful, so it assumes that by running the LabVIEW merge tool you must have merged correctly.
For a number of years, this set of scripts has assisted LabVIEW developers in handling these issues. Install instructions are available on the website. In an attempt to make these same scripts work for the command line, SourceTree git, and SourceTree mercurial, this branch was created. This development was partially successful, but not as complete as the original scripts. To solve the problem, a small labview tool was developed for performing the diff and merge. This is located here, along with instructions for how to build and install it: