Upgrade of 10.04 to 12.04

[Geoffrey]

I wish to upgrade from 10.04LTS to 12.04LTS so I consult the Ubuntu
website for the simple instructions on how to do so. The paper-chase
begins.
I follow the simple guide via the 'upgrade' link to find: 'Upgrade from
Ubuntu 11.10 to 12.04LTS"
I go the the link 'read the upgrade notes' (for versions other than
11.10). There are many listed but none that refer to upgrading 10.04LTS
to 12.04LTS.
The paper-chase seems to end here with no result.
I believe that upgrading should be done with care using the right
instructions depending on the system version being used so I am
reluctant to take a punt and mess things up.
Surely I don't need to upgrade from 10.04LTS to 10.10, then to 11.04 and
then to 11.10 before upgrading to 12.04LTS?
I would be grateful for advice from members.
PS My Update Manager does not advise that 12.04LTS is ready to load.
Geoffrey