That doesn't make sense. You mean "a blog is traditionally meant to include the things you did do, not the things you didn't", shurely?
Are you always this pedantic when you are sober?
It depends on which bit is "the other way round".
For example:
- a blog is traditionally meant to include the things you did do, not
the things you didn't do.
- a blog is traditionally meant to include the things you did do, not
omit the things you didn't do.
- a blog is traditionally meant to include the things you did do, not
not meant to include the things you didn't do.
Or we could apply the "not" to the noun "blog".
- I believe a blog is traditionally meant to include the things you did do, not
something that is not a blog is traditionally meant to include the things you did do.
Or we could apply the "not" to the verb "believe".
- I believe a blog is traditionally meant to include the things you did do, not
disbelieve a blog is traditionally meant to include the things you did do.
Go on: go for it!