Including JSP page in Vm file

$theme.include($themeServletContext, "/elements.jsp")

make sure that elements.jsp page is available under root folder of theme

Adding Portlet in Control Panel

In liferay-portlet.xml .......write these two lines after <icon>/icon.png</icon> tag

       <control-panel-entry-category>configuration</control-panel-entry-category>

        <control-panel-entry-weight>1.0</control-panel-entry-weight>