In the "page options" which is in the File Menu you have a "Custom Page Size" make that page size to your landscape ticket size. You can lock that page size so that every extra page will be the same size giving you the option of making each ticket different. You can also make your basic design a "Live Copy" which will make your life easier and stop this standing on your head/turning laptop. Here is a copy of part of the Help file: Live Copies give you a way of having multiple copies of an object that are linked together so that if one copy is changed they all change. However each Live Copy can be transformed independently, so for example you could have larger and smaller versions of the same Live Copy, or perhaps copies with different rotations.

Once you have all of your designs done start a new doc in A4 portrait put in your guides/grid. For tickets I use rectangle drawn in the guide layer and drag + right click with the mouse to duplicate till your sheet is full. With this done open your ticket design file and Ctrl+C each page design into your Guide/template doc. and do a quick rotation of -90 degrees. Doing this way only really stops you rotating your laptop. If your going to be doing a huge amount of these cards I would seriously think about using a DTP programme and if it is just changing text in each of the cards/tickets you could import a CVS file into the programme to a field where you want the text to change. Hope that helps your problem!