1. Create a seating surface

Select the cylinder in the [Primitive] command, specify the size and number of divisions, and create.

I apply a bit of work on the seat surface.

I select faces of the top surface in the [Select] command.

Extrude by the [0] offset in [Menu > Selected > Extrude faces].

Reduce the size in the [Property] in the [Scale] command.

Cut a little outside the shrunk faces by [Continual cut] in the [Knife] command.

And cut the new face by the [Knife] command.

You can cut in the middle of the two points with [Shift] key at this time.

And select the created middle lines by the [Edge loop] in the [Select] command.

Move them to a downward direction slightly by the [Move] command in order to make a dent in.

Select the border lines beside the dent by the [Edge loop] in the [Select] command, and set the weight values by the [Weight] command.

Set the weight values to the outer lines in the same way.

It is the completion of the bearing surface.

2. Create a backrest

Next is to create a backrest.

Click [New] in the [Object Panel] to create a new object. And create a cube by the [Primitive] command.

Now transform the shape of the backrest by the [Bend] command.

At first, switch to the front view. After selecting the [Bend] command, extend the guide around the center of the cube.

Then drag away a little from the guide, and bend about 90 degrees downward.

Next, switch to the top view, and bend in the same way.

Delete the faces at both ends because they are not necessary.

Select the corner lines by the [Edge loop] in the [Select] command to round the corner.

Execute the [Bevel] command with the values described in the following image.

Since vertices on the rounded edges created by [Bevel] are away, Use the [Menu > Objects > Join closed vertices] to combine them that are close position.

Set a mirroring in [Prop](Property) in the [Object panel], and then freeze the mirroring by [Menu > Object > Freeze].

Select the faces of the backrest like the following image, and delete them.

Next, create a new object.

Select [Bridge] in the [Hole] command, and select lines around the deleted faces. [Bridge] dialog will be shown. Specify a segment and a tension, and press [OK] button.

Now round the newly created part. Select lines, execute the [Bevel] and call [Join Closed Vertices].

Holes are shown around the deleted faces because the corner of the bridge is rounded.

Select the entire backrest, and move them in the side view. Now the backrest is completed.

3. Create legs

I will continue to make a leg this time.

Create a new object in the [Object Panel], and create a cylinder by the [Primitive] command.

Select the center point at the top of the cylinder, and heap it up.

Next, enlarge the middle part of the cylinder.

After selecting the lower half of the cylinder, rotate along [X] axis and [Z] axis like the following image.

I make a rod that connects the front leg and rear one.

Create a cylinder in a new object by the [Primitive] command.

Rotate and enlarge it in the same way as the legs.

Set the mirroring.

A bar connecting the right leg and left one can be created in the same way.

It is the completion of a small chair in this.