Many ways to achieve this, try each and pick one that suits your need best. Also, be aware that depending on how you've designed your package you may need to edit it on the new server to change servernames, filenames, etc...

1) Edit the package in Enterprise Manager and choose Save As...

2) Transfer the rows from sysdtspackages as explained here (http://www.sqldts.com/default.aspx?204)

3) Use a tool like DTSBackup2000 (http://www.sqldts.com/default.aspx?242)