Not too complicated. A keyframe is plotted with each move. After the first one is entered with the green + sign, each succeeding grid move plots a new keyframe. Click this button if the grid isn't shown...
Use the mouse to drag/size the grid in the preview window.
Check out that help file linked above.
For protection, Save Project File AS routinely, giving it a unique # or name, so as not to overwrite prior saves. Using Save Project Files (no AS) will overwrite. From the HOME tab, that choice is available by clicking the caret to the right of the Save Project button on the toolbar.