I’ve been asked few times how do i format my code. I try to stick to a easy to read and understand style. Sometimes i do, sometimes i don’t. Let’s talk first about those times i do 
CSS Code
Each child is indented with a tab. So, i have this style:
#header {
}
#search {
}
#search button {
}
When you read only CSS you know that #header is the parent, #search is his child and the parent for button. Easy to read, easy to understand, right? 
I try to avoid code like:
#parent #another_parent #header #search button { }
Because is kinda bogus.
I saw some guys who wrote their code on single line, without any indentation. Even if you have a less KB file, the result is hard to read and edit. Even though, i use very rarely one line code when i have to add one-two rule to a selector ( something like .element { color:red } ).
HTML Code
Actually… Somehow, i have same rule here: every child have a one tab indent:
As an extra info: when i have large blocks of code (div, forms), on closing tag i add a comment with the id or class name: if the block has a class, the closing comment is /.class name and if is an id /id name
Again, easy to read and to maintain, especially when you reuse some of your code.
Javascript/jQuery Code
Well.. Probably is already clear enough how do i do:
function function_name() {
var someVar = 1;
if( someVar === 1 ) {
alert('someVar is 1!');
for(i=0;i<10;i++){
alert(i);
}
} else {
alert(':(');
}
};//function_name
Conclusion
The main keywords are: indent and comments. You don't have to overuse indent, because the code will be impossible/hard to read. Also, don't over-comment your code. Don't comment the obvious :
var foo = 'bar'; // the 'foo' get 'bar' value
Well.. I can't say nothing else but „happy coding!”.
