If you cant get them into the back then you just gotta try and put them so that first turn charge leaves your opponents line as awkward as possible.
Lizardmen 2500 Oldblood +piranha blade +talisman of preservation +cold one +shield Scar veteren +shield +light armor +great weapon +BSB- Razor...
A horde-brick of saurs with spears and the skavenpelt banner. Put a skink priest on the corner so when you maximize frontage he gets shoved out of...