Year 12s: what will be the first way you research your future options? >>

Help! I've been lazy for 3 years. My job prospects are dull

I'm currently a postgraduate student and I'm looking for graduate jobs. But all I have on my CV is one internship (in equity research) that I got through contacts and being a volunteer tutor for like 6 months. The rest is just relevant projects I did at uni, and some single day only jobs. And a few other things like small achievements and extracurriculars. I was too lazy to apply for a spring week in year 1 of undergraduate, and in year 2. I've never even been on a society committee. I just participated, but never got involved further. I mean sure I have one internship under my belt but I still feel useless compared to a lot of my friends who have jobs, or have had 2 3 or 4 internships. If only I had payed attention from year 1 I wouldn't be in this mess. Can anyone help me on what to do. A few things I was thinking about are:

I'm applying to grad schemes in equity research because that's basically one strong point my CV has. But I also want to look into other areas such as IB and actuarial science. Best route for these? I've managed to find some internships in October next year for IB after my master's ends so I'm literally applying to whatever I can right now and I'll decide later whether to explore IB or go straight to equities.

Finally, two more questions. Should I apply to summer internships, since I'll be working on a dissertation then or just the grad schemes and off cycle internships? And what about spring weeks? Just to have something more on my CV. Is it even possible to get those as a postgraduate student? Is there anything else I'm missing, ways to enhance my CV rapidly.