How to prepare for corporate strategy & development internship/probation?

As per title, what are the most important things to do in order to secure a return offer/confirmation in a corp strat & dev team.

I understand there are many such guides for IB and there are likely advice that work for both roles such as attention to detail, hard work and willingness to learn. But there’s also obvious key differences such as the hours as well as cs+d not really having a formal training program. Aside from what, for people in the industry, what are the important things to know and prepare for that are more specific to cs+d.

I am especially curious about modelling readiness given no formal training program and have read that it is good to be able to build an operating model from scratch as their existing models might be non-industry standard and hard to audit.