Git Ignore (global)

Create the file ~/.gitignore as shown below

# Folder view configuration files
.DS_Store
Desktop.ini

# Thumbnail cache files
._*
Thumbs.db

# Files that might appear on external disks
.Spotlight-V100
.Trashes

# Compiled Python files
*.pyc

# Compiled C++ files
*.out

# Application specific files
venv
node_modules
.sass-cache

followed by running the command below, in terminal:

$ git config --global core.excludesfile ~/.gitignore

to not track files that are almost always ignored in all Git repositories.

Or simply download macOS specific .gitignore maintained by GitHub itself and put contents of it to ~/.gitignore.

Note: You can also download it using curl

curl https://raw.githubusercontent.com/github/gitignore/master/Global/macOS.gitignore -o ~/.gitignore