Or, you can move the mouse pointer to the left of the first character in any line of the paragraph you want to select. When you do this, the mouse pointer turns into an arrow pointing up and to the right. Now double-click with your mouse and the paragraph is selected.
If you are a keyboard short cut fan, you can select the current paragraph by pressing Ctrl+Up Arrow (this moves the insertion point to the beginning of the paragraph) and then pressing Ctrl+Shift+Down Arrow.