Beginner Html Question- Please Help!

[Moses]

hi all

I've been given the files thankyou.html and style.css. After changing the wording to my own using NVU and saving, when I upload thankyou.html via filezilla to my site, the wording appears but the page doesn't look the way it should. Apparently I'm suppose to do something with the style.css file but I don't know what. Can anyone help? These are the steps I've taken

step 1- save thankyou.html on my desktop
step 2- open nvu
step 3 open thankyou.html from my desktop using nvu
step 4- change the wording to make it my own
step 5- save the thankyou.html file so it now includes my words instead of what was previously provided on the page.
step 6 - close nvu and open filezilla
step 7- sign into filezilla. click on the mydomain.com public html.
Step 8- drag and drop the file thankyou.html from my desktop to mydomain.com so I now have mydomain.com/thankyou.html as a file.

I havent done anything with the style.css file. I don't know what to do with it. What should I do with it? Should I be pasting it somewhere in "source" via nvu? I just need to know what to do in order for the format of the page to appear correctly.

I've looked up some stuff online and tried several different things and nothing has worked so far. I'm sure its something simple that I just can't figure out. Can someone tell me the exact steps that should be taken?

Will hit the thanks button for anyone who can help me get this right. Thanks in advance