MT4.3は標準でページ分割機能が付いています。以前のバージョンでは「PageBute」や「MTPaginate(PHPを使用)」などのプラグインを使う必要がありました。
カテゴリアーカイブと月別アーカイブに、ページ分割機能をさくっと付ける方法を紹介します。

記事の概要を下記のコードでサンドするように設置するだけです。

<mt:Ignore><!-- ページ分割2ページ目以降の記事の表示数（mt-search.cgiを使用）$list_on_indexでauto扱い --></mt:Ignore>
<$mt:Var name="entries_per_page" value="3"$>
<mt:Ignore><!-- Construct the url for querying entries. --></mt:Ignore>
<mt:SetVarBlock name="search_link">
	<$mt:CGIPath$><$mt:SearchScript$>?IncludeBlogs=<$mt:BlogID$>
	&template_id=<$mt:BuildTemplateID$>
	&limit=<$mt:Var name="entries_per_page"$>
	<mt:If name="archive_template">
		&archive_type=<$mt:ArchiveType$>
		<mt:If name="datebased_archive">
			&year=<$mt:ArchiveDate format='%Y'$>&month=<$mt:ArchiveDate format='%m'$>&day=<$mt:ArchiveDate format='%d'$>
		</mt:If>
		<mt:If name="category_archive">
			&category=<$mt:CategoryID$>
		</mt:If>
		<mt:If name="author_archive">
			&author=<$mt:AuthorID$>
		</mt:If>
	<mt:Else>
		&archive_type=Index
	</mt:If>
	&page=
</mt:SetVarBlock>
<mt:Ignore><!-- Strip spaces and trim value. --></mt:Ignore>
<$mt:Var name="search_link" strip="" trim="1" setvar="search_link"$>
<mt:Ignore><!-- Entries loop for publishing static and dynamic pages. --></mt:Ignore>
<mt:Entries limit="$entries_per_page">

【記事の概要をここに入れます】

</mt:Entries>
<mt:Ignore><!-- ページ分割時のナビゲーション Condition based upon if page is statically or dynamically rendered using the search_results variable. --></mt:Ignore>
<mt:SetVarBlock name="pagination_navigation">
	<mt:If name="search_results">
		<mt:Ignore><!-- Navigation for dynamic pages (same as navigation found in the Search Results system template). --></mt:Ignore>
		<mt:IfPreviousResults>
			<a href="<$mt:PreviousLink$>" rel="prev" onclick="return swapContent(-1);">&lt; Previous</a>&nbsp;
		</mt:IfPreviousResults>
		<mt:PagerBlock>
		<mt:IfCurrentPage>
			<$mt:Var name="__value__"$>
		<mt:Else>
			<a href="<$mt:PagerLink$>"><$mt:Var name="__value__"$></a>
		</mt:IfCurrentPage>
		</mt:PagerBlock>
		<mt:IfMoreResults>
			&nbsp;<a href="<$mt:NextLink$>" rel="next" onclick="return swapContent();">Next &gt;</a>
		</mt:IfMoreResults>
	<mt:Else>
		<mt:Ignore><!-- Navigation for statically published page. --></mt:Ignore>
		<mt:If name="archive_template">
			<$mt:ArchiveCount setvar="total_entries"$>
		<mt:Else>
			<$mt:BlogEntryCount setvar="total_entries"$>
		</mt:If>
		<mt:Ignore><!-- If blog contains more entries than the number of entries to display per page. --></mt:Ignore>
		<mt:If name="total_entries" gt="$entries_per_page">
			<mt:Ignore><!-- Set the total number of entries to iterate through the pages. --></mt:Ignore>
			<mt:Ignore><!-- IF ` divided by entries per page is a whole number. --></mt:Ignore>
			<mt:If name="total_entries" op="%" value="$entries_per_page" eq="0">
				<mt:Ignore><!-- Set total pages to total entries divided by entries per page. --></mt:Ignore>
				<$mt:Var name="total_entries" op="/" value="$entries_per_page" setvar="total_pages"$>
			<mt:Else>
				<mt:Ignore><!-- Get the remainder when dividing total entries by entries per page. --></mt:Ignore>
				<$mt:Var name="total_entries" op="%" value="$entries_per_page" setvar="remainder"$>
				<mt:Ignore><!-- Subtract remainder from total entries. --></mt:Ignore>
				<$mt:Var name="total_entries" op="-" value="$remainder" setvar="total_entries"$>
				<mt:Ignore><!-- Determine total pages by dividing total entries (minus remainder) by entries per page. --></mt:Ignore>
				<$mt:Var name="total_entries" op="/" value="$entries_per_page" setvar="total_pages"$>
				<mt:Ignore><!-- Add one page to handle the remainder of entries. --></mt:Ignore>
				<$mt:SetVar name="total_pages" op="++"$>
			</mt:If>
			<mt:Ignore><!-- Loop through total pages, creating links to all but the first page (which is the current page). --></mt:Ignore>
			<mt:For from="1" to="$total_pages" step="1">
			<mt:If name="__first__">
				<$mt:Var name="__index__"$>
			<mt:Else>
				<a href="<$mt:Var name="search_link"$><$mt:Var name="__index__"$>"><$mt:Var name="__index__"$></a>
			</mt:If>
			</mt:For>
			<mt:Ignore><!-- Hard-coded link to the next page (page 2). --></mt:Ignore>
			&nbsp;<a href="<$mt:Var name="search_link"$>2" rel="next">Next &raquo;</a>
		</mt:If>
	</mt:If>
</mt:SetVarBlock>
<mt:Ignore><!-- Strip space and trim navigation code. --></mt:Ignore>
<$mt:Var name="pagination_navigation" strip=" " trim="1" setvar="pagination_navigation"$>
<mt:Ignore>HTML出力</mt:Ignore>
<div class="content-nav">
<mt:Ignore><!-- Output variable if exists. --></mt:Ignore>
<$mt:Var name="pagination_navigation" strip=" " trim="1" setvar="pagination_navigation"$>
<mt:If name="pagination_navigation">
	<div class="pagination-navigation">
		<$mt:Var name="pagination_navigation"$>
	</div>
</mt:If>
<mt:Ignore><!--デフォルトのフッター-->
<mt:ArchivePrevious><a href="<$mt:ArchiveLink$>">&laquo; <$mt:ArchiveTitle$></a> |</mt:ArchivePrevious>
<a href="<$mt:Link template="main_index"$>">Main Index</a> |
<a href="<$mt:Link template="archive_index"$>">Archives</a>
<mt:ArchiveNext>| <a href="<$mt:ArchiveLink$>"><$mt:ArchiveTitle$> &raquo;</a></mt:ArchiveNext>
</mt:Ignore>
</div>

あとは、CSSで見た目を変更

.pagination-navigation	{
	font-size: 80%;
	text-align: center;
}

参考させていただいたサイト