Go through this guide and follow step-by-step instructions to make a Swinging Garden Bench.
The first thing you need to do is to place a stone brick wall on the ground and three birch fences at its top. Then place a stone brick wall at the top of the fences.
Then you have to place a spruce trap door at the top and spruce slabs leaving a gap of one block at the top of trap doors.
After this, hang birch fences under the trap doors and attack birch fence doors in the same way as shown in the image below.
The next thing you need to do is to place three iron bars under the birch fences.
Now you have to make a bench. Use spruce trap doors in the same way as shown in the following image to make a bench.