Hi Deanandre64,
As Jimbo said a good place to start is the DMQ website.
You will find a list of organisations who you can choose to register with.
I believe that there are some small variances in how much your registration will cost and you should put in a call to a few of them to see who suits you best.
They will talk to you about your experience to date and double check when you passed your DSC1 as they dont recomend you jump from DSC1 to DSC2 straight away and for good and sensible reason.
Who ever you choose will take your DSC1 registration number and send you out a registration pack giving you some further advice and requesting a cheque from you, the form completed and a couple of passport type photos duely signed and dated on the back.
Once you've sent it back, they will turn it around and forward your DSC2 portfolio to you along with a country wide list of acredited witnesses/assesors for you to reach out to and arrange your witnessed stalks and full details of what you will be checked and questioned on.
The rest is up to you.
Hope this helps
Robbo25