If you want to bypass all automated means for more control, you can create a key and certificate request using the following commands:
/usr/bin/openssl genrsa 1024 > private.key /usr/bin/openssl req -new -key private.key
where you can replace 1024 with 2048 if you want a stronger key. The genrsa will ask you all information for the certificate.
Once created, you give the certificate request to a certificate authority. They'll give you a new certificate, which you'd use with your private.key to make the pair.