pockettphoto on "Add New Gallery (missing Add Images)"

Hi,
Since updating to 3.5, I no longer know how to add galleries. Note I am not amazing with WP software, and am no good with codes etc.
I am able to upload media to my library, but when I go to create a page, I need to select a gallery and am not sure how to get the images onto the page. It was so easy before updating.
Hope that makes sense, would love some help here :)
Regards,
Daniel