Well if you would like to still work after you have retired the amount of money you make could impact your retirement benefits and sometimes it would be a good idea to not work. Talk with an accountant and consider the tax advantages and disadvantages of working part time during retirement.
If you do decide to work during retirement there are plenty of options. Substitute teaching is a good option if you can deal with younger people and it is easy to deny if you don’t want to work that day since substitute teachers are put on an automated phone service that requires you to push a button to accept or decline.
If you don’t have computer skills it would be a good idea to learn some and maybe you could find a way to work from home. If you are a good writer you could be a freelance writer and there is always a need for clerical/ office work or receptionists. If you are an experienced retiree from a line of work you could be a consultant and provide advice and guidance for existing companies. Just because you have retired does not mean that you are no longer a professional. Mostly it is important to find something that you could enjoy doing or items you enjoy making and selling.
The idea of retirement is to stop working so you can enjoy life more so try to find something that lets you enjoy life more.