Confused with Unnatural Linking

Hi,
I'm reading/learning about the importance of mixing anchor text. From what I read they suggest using keyword, mix keywords, domain, www, etc..
I've been doing this and not sure I'm correct. The domain has the keywords in it, if I mix up words the keywords are still there. For example, let's say the main keyword is Toyota Parts.
I use anchor text Toyota discount parts, Toyota genuine parts, toyotapartsdomaincom, toyotapartsdomain, wwwtoyotapartsdomaincom, etc..

Is this considered unnatural links becuase the words 'Toyota' and 'Parts' are in each link?
Or is the example above correct for natural linking?

That's fine, different variations are considered different keywords - even singular and plural. Also to make things look even more natural don't just keywords, but also mix in some terms like: click here, visit here, check this out, etc.