Download Jasper reports from here:
http://www.sugarforge.org/frs/?group_id=193

JasperReports for SugarCRM is a Java web application, so it requires a
Java run time and an application server.  The Tomcat application server
is included, so the only prerequisites is a Java Virtual Machine, version
1.3 or later.
Install the jre/jdk and set the JAVA_HOME invironment variable.

Unzip the downloaded zip file, it will create one dir catalina.

Change in the catalina/conf/server.xml file
(Text in bold need to be change according to your sugarcrm)
********************************
<GlobalNamingResources>
        <!– SugarCRM database registered with JNDI.  This needs to be –>
        <!– a global resource so we can use it to authenticate        –>
        <Resource name=”jdbc/jasperreports-sugarcrm” auth=”Container”
                  type=”javax.sql.DataSource”/>
        <ResourceParams name=”jdbc/jasperreports-sugarcrm”>
            <parameter>
                <name>factory</name>
                <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
            </parameter>
            <parameter>
                <name>username</name>
                <value>Sugar_database_user_name</value>
            </parameter>
            <parameter>
                <name>password</name>
                <value>Sugar_database_password</value>
            </parameter>
            <parameter>
                <name>driverClassName</name>
                <value>com.mysql.jdbc.Driver</value>
            </parameter>
            <parameter>
                <name>url</name>
                <value>jdbc:mysql://localhost/Sugar_database_name</value>
            </parameter>
        </ResourceParams>
</GlobalNamingResources>
***************************

Now run the tomcat application server.
$cd catalina/bin
$./catalina.sh start

And point your browser at:
http://localhost:8080/jasperreports-sugarcrm/login.jsp

Login as sugar user/password