Academic 'rehabilitation' after poor undergraduate results
I can't speak to Philosophy programs so this may not be terribly useful to you, but in general, if your grades/marks are not stellar, and you exams are not either, then you should probably rely more on the power of recommendations from people who know your good traits well.

There are probably several ways to do this, and though I'm not sure about philosophy, in the sciences for example, a couple of years of volunteering in laboratory with one or two different researchers and making yourself invaluable to them can garner you major points.

I didn't do wonderfully in my studies either, and my exams were not fabulous, but I spent three years after graduating my undergraduate university volunteering in two different labs, and enrolling in evening courses to (a) try and do better in essential courses pertinent to my area and (b) demonstrate that I was serious about graduate studies because of my initiative in taking all these courses.

I ended up with three great letters and job opportunities, and later grad school (PhD) through working with these professors.

However, a word of caution: If your weaknesses really include motivation and work ethic, then post graduate study is not going to be fun for you. It's completely different than undergrad as there is way less structure, and you have to be very self-motivated, make your own deadlines, work all the time without people asking you to, and complete projects on your own. It's really hard. If you do decide that you can do it though, I suggest finding an advisor who will be more hands on.

Hope this helps a little!