Public DNS

[disco_stu]

I just recently purchased a domain name, unaware that dns hosting was
not included.  Once I learned that, I used Public DNS to try to set up
the dns to work.  At the place where I purchased my domain name,
omnis, I switched the servers from their servers to the public dns
servers 1 and 3 as primary and secondary.  I guess my question
is...what did I do wrong?  My goal was to have the server take every
request for my domain name and link it to my ip address, and then go
there to my website, but it doesn't come up.