When i first joined CHD i keept 100-200 GB free on my HDD, Downloaded 20-30 or more movies usualy 720p because there smaler than the 1080p or full bluray. and seed them 10-12 hours a day for a month and i passed the test in 3 weeks with 1 week to spare
All you need is:
-some free space on your HDD
-decent net speed so you can download/upload in a decent anount of time
-keep your pc open 10-12 hours a day minimum.
-enjoy your account after you pass the test and waith the next assesment (usualy 2/year)