This page describes the Gate Tool.
Gates allow your Sims to enter and leave through a fence.
Gates are place on existing fences. To place a gate, click on the Gate Tool.
Select the desired gate and place it on a fence.
There is a huge selection of gates from which to choose. Too see them sorted by style, have a look in the Gates section of the Object Catalog.
Gates are not recolorable, so a gate has to be made in each color. In the gates that come with the game you will find several colors of the same style for this reason.
Many gates go well with several fences, but some seem suited only to particular fences. Experiment to find a combination that works for you.
To delete a gate, select the Hand Tool, click on the gate and press Delete. Or if you want to remove a fence with a gate, delete the fence and the gate will be deleted as well.
To get a good idea of some of the gate possibilities, look at some of the pre-made lots. They will give you some ideas of what is possible.