For fastenings or finishing
Chairs benefit from buttoned cushions whether they are for added comfort, decoration or fastening.
Hard based chairs such as some dining room or outside metal chairs usually benefit from the addition of thin or squab cushions. These can be plain or in some cases to add a bit of decoration they can be buttoned.
The buttons also help to keep the filling in place especially if the traditional type is used like horsehair or feathers. This cushion is used in the more traditional ways like on occasional chairs or bench seats and usually are not washed very often.
These cushions usually have no fastenings as the buttons are sewn in place when the cushion is finished. The opening is usually slip stitched closed.
These could also be used with modern fillings and have the same look and if they needed to be washed the buttons could be removed.
Self covered buttons are usually used to match in with the fabric. These need to have a shank so they can be sewn tight against the cushion. For more strength an extra button can be used underneath. Sometimes these are clear buttons but if the cushion is going to be reversible then another self covered button will have to be used.
When the cushion is finished, mark the places you want the buttons to go on both sides of the cushion.
You will need to use a long needle and strong thread, it is probably best to use double or triple threads. Tie the thread to the shank of the button and then push the needle through the mark on the top to meet the mark at the bottom. Tighten the button and secure thread. If using another button on the bottom then sew that separately over the thread of the first.
Buttons can be used as decorating a cushion cover.
This is done by using small buttons to make a picture for example green buttons for trees.
A contrasting button can be used to highlight a colour in the cushion fabric or a darker shade of buttons used on a lighter coloured cover.
If the buttons are used purely for decoration then make sure they don't stand too proud as then they may be uncomfortable.
Buttons that decorate a cover can also have a dual purpose by fastening the cover as well.
These covers would have the opening along the front edge(s) or diagonally across the front. The buttons would then act as part of the decorated cover.
There are lots of ways to make buttoned cushions both either for fun or to provide a function as well.