Request a user certificate by following the instructions on the Dutchgrid Certification Authority website. A good starting point for finding your certificate authority if not available from this site is: https://www.eugridpma.org/members/worldmap/ (Europe) or http://www.igtf.net/ (World wide). Contact Science Data Centre Operations group if none of the above works.
Install the certificate by following the instructions provided by your certificate authority. Typically this involves:

Save the mail with the signed certificate as $HOME/.globus/usercert.pem and make sure that the userkey.pem file in that directory contains the pricate key that matches this certificate. As these *.pem files are strictly personal, their permissions should be set properly by the following command:
> chmod 600 *.pem
Load the certificate into your web browser. See e.g. http://ca.dutchgrid.nl/info/browser for instructions.
Apply for authorization to use LOFAR resources:
- https://voms.grid.sara.nl:8443/voms/lofar for access to the LOFAR LTA storage.

Installation of certificates