Just hit your <enter> key and use the spacebar to indent. I've not seen a standard per se as to how to properly format SQL statements, but it makes it much more clear (and easy to edit) if it's not all bunched together.
Now, if you're talking about SQL within a PHP script, I find the overall best solution (not in every case, mind you) is to use HEREDOC syntax, e.g.
$sql = <<< END_SQL SELECT column1 , column2 , date_column FROM sometable WHERE pkID = 1024 END_SQL;
The limitation is that the end statement (in this case END_SQL, can be anything you want) has to be on a non-indented line. So it's great for a script that doesn't have a bunch of conditional blocks that have to be intented. Unfortunately the syntax highlighter has a problem so it doesn't 'pop' as it should, but it works great. Easy to edit, not to mention allowing you the ability to have a HUGE multi-table JOIN that you can actually decipher.
Second best method, IMHO is to simply use PHP's ability to ignore whitespace as Pete pointed out.
I just tend to split mine over multiple lines if it's a long query to make it more readable than 1 long line.
SELECT `a`.`articleid`, `a`.`title`, `a`.`content`, `m`.*
FROM `articles` AS `a`
INNER JOIN `authors` AS `m`
ON a.authorid = m.authorid
WHERE (m.name = 'Alan') AND (a.created > 1204205135)
ORDER BY `title` ASC
As long as it's readable it doesn't really matter how you format it
SELECT t1.col1, t1.col2, t3.col3
FROM tab1 as t1, tab2 as t2
LEFT JOIN tab3 as t3 on t3.colx = t1.col1
WHERE t1.col1 = cond1
AND t1.col2 = cond2
GROUP BY t1.col1, t1.col2
ORDER BY t1.col1, t1.col2 ASC