ECM Guys Please Help - Assessment Centre Capital Markets London

Hello Everyone,

I just got called for an AC at a BB for an off-cycle internship in London within the global capital markets division. My goal is ECM. 

Apparently, the individual case will be about a UK company listed on LSE that wants to finance with equity its expansion to the US and wants to increase its capital by issuing a rights issue. Historically financed with debt has not been on the equity market for a while, You have to structure the key terms by making relevant considerations. Updates on market conditions are given.

Now, my question is how do I prepare for it? 

I have a good understanding of ECM products including rights issues (TERP etc) but on how to structure I have no clue and can't find anything online (really). How do you decide how many additional shares, how do you decide if the needed amount is feasible and all other considerations? 

It would be really interesting to know from you any input or material you find valuable

Thanks in advance!