it really depends upon how complicated your situation is, what level of stress you are under and whether the creditors are at the final stages with bailiffs etc.
The procedure in its simplest form is to fill in a Statement of Affairs ( 32 pages ) and a Bankruptcy Petition ( 2 pages) and phone your local court to make an appointment.
each court has slightly different procedures so if you ask the bankruptcy clerk to go over these then you will be sure to follow the right procedures for your court.
Paul Johns Assisted Bankruptcy Specialists Reviva UK www.revivauk.com
As you were talking about insolvency rather than bankruptcy - which is just one solution to deal with insolvency - do make sure that you consider other options such as a DMP or IVA. It may be sensible to discuss this with an insolvency practitioner, who is qualified and licensed to give advice on all insolvency options and solutions.
For an informal chat about any financial difficulties, or advice as to the options available, I can be contacted via my website - www.melaniegiles.com