What's the basic steps if I want to add my own components which will be used in markdown?

[ohstackoverflow]

I tried to add one component into /components/app/mycomponent.vue.
But as result, I got an error:

[Vue warn]: Failed to resolve component: mycomponent
If this is a native custom element, make sure to exclude it from component resolution via compilerOptions.isCustomElement.

Any comments are welcome. Thank you.