1- Setup the two devices in active/active mode (as I don't even see the options any where)it is done by creating more than one traffic group.
Manual: BIG-IP Device Service Clustering: Administration
http://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/bigip-device-service-clustering-11-2-1.html
3- I know I have to enable network failover so ok I do that do I need to connect the TMM switch ports for the failover options to show up or like connect the two interfaces via cross over cable like 1.1 of Unit 1 to 1.1 of Unit 2?if you have only two units, you can use cross over cable connecting them back to back.
hope this helps.