Setting oneself up for an eventual MBA. The MBB route?

At this point in my career I am an undergraduate engineering student trying to figure out what my summer job should be. I started researching consulting last year and ended up applying to MBB, Deloitte, Accenture, PwC etc. Within management consulting I was able to land interviews with 2 of MBB, but was not selected to interview within mc for any of the other firms. This might have been due to my concentrated networking efforts.

Although I wasn't able to get an offer (made second round at one of the two firms), I have come out confident that I have the potential to work at one of MBB. The question that does keep coming up for me though is what do I do now to prepare for full time? The biggest decision for me to make is the option of pursuing a technical internship or going down a more business internship route. I want to have a fun and exciting summer, with meaningful work, and while at it set myself up for full-time recruiting in the fall.

If I go down business, I have some options for applying: Accenture Tech & SI, JP Morgan, Capital One, Business/Leadership Dev at a couple Fortune 500 firms.

For more in the industry side, I could pursue startups or some of the bigger names on the west coast.

What do you recommend I can do to set myself up for an eventual MBA? As far as my knowledge, the most direct route seems through MBB.