Validation Help

Hello All
I’m new to WordPress blogging and know little to nothing about css and xhtml coding. And I’m hoping someone here can give some guidance on how to go about validating my web site @ http://painreliefforback.com. Warning, new to the blogging community so there’s not much to see there. Don’t want to waste time and effort on something not working correct. Really would like to get the bugs worked out first. Thanks in advance for all helpful tips, comments and suggestions.
araymond