how to code pagination?

hello

I edited my category.php to list only the titles of my post.

<?php $postCount=0; ?>

 <?php
 $categoryvariable=$cat; // assign the variable as current category
 ?>

<ul>

<?php $myposts = get_posts('category=' . $categoryvariable. '&numberposts=500&offset=0&order=ASC&orderby=post_title');
	 foreach($myposts as $post) :
	 setup_postdata($post);
 ?>

<div class="entry">
	<li>
		<a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>"><?php the_title(); ?></a> @ <?php the_time('m/d/Y g:i A') ?> <?php edit_post_link(' | Edit'); ?>
	</li>
</div>

	 <?php endforeach; ?>
</ul>

As you can see, i set the numberpost to 500 so all my blog titles will be listed. However what i really want to do is display the first 100 then the next 100 will be displayed in “page 2” then the next 100 in page 3 and so on

i dont know how to divide these so i will have page 1, page 2 , page 3

can anybody help?

Thanks!