Edit page in text mode problem

Hi
I have a contact page and I want to move some elements(float) so I decide to edit the page in Text mode,not Visual and add some div-s to use them in CSS.
After I’ve done,all seems to be nice,but then I return to the page in Visual mode to add one new line:as in image I’ve hit Enter key after text “Telephone numbers :” ,then in the html code,current div was closed and added again on the next line,in this case floating elements not working as before,ok I can fix that but is the right way I’ve done?

I could have multiple elements to edit,it is hard to return to code to fix all extra html code added,there is something I’ve done wrong?
There is a screeshot I’ve done:
https://img266.imageshack.us/img266/5439/8r2w.png

Thanks!