For simulating a completely blind user, you could put on a blindfold and try out the software after turning on your desktop's accessibility features. I think there are resources for simulating different kinds of color vision. Also try using your app with one hand. And with no hands but a joystick or other device you use without your hands.
This is a really good start! Good list of possible testing avenues :)
I'm sure that the blind community has UX conventions documented or otherwise that would be best practice to stick to, but may be very hard for seeing people to understand or know off the bat. I definitely think abled people should test accessibility, but no replacement for getting feedback from the target audience.
I'm maintainer of WeKan Open Source kanban https://wekan.github.io
I'm trying to add accessibility to WeKan etc, but problem is, how do I get contact to blind community to understand how to help.
Accessibility issue is at https://github.com/wekan/wekan/issues/459
Or someone can email me, address at https://wekan.team/commercial-support/