<?php $i=1; if (have_posts()): while ( have_posts() ) : the_post();
if($i==1){ ?>
... code for the first post ...
<?php } if(($i>1)&&($i<5)) { ?>
... code for 2nd, 3rd, 4th post ...
<?php } if($i>4) { ?>
... code for 5th, 6th, 7th, 8th post ...
<?php } $i++; endwhile; endif; ?>
^ This is to display posts with different styles