I've just started to collect some specialists' advice that may have helped Sherlock disappear. I've found so far:

Irene Adler:
Find out what the record-keeper of DNA tests likes.

Mr. Ewart of Janus Cars:
All you need is to hire a car (even a laundry truck) and donate some of your blood (most suitable exactly a pint). Placed in the correct position it will create the impression that you are dead and help you disappear to South America or elsewhere.

Jim Moriarty:
Find an actor who takes on your role. If the money is good he will make people forget that you even existed.
Find an ordinary live-in person who sees but doesn't observe.

Joe Harrison:
Find a railway track without points.

Jeff, the cabbie:
Find a proper genius cabbie who knows places even you weren't aware of their existence.

James Philimore:
Pretend to collect your umbrella.

Hänsel and Gretel:
Vanishing is easy if you let a wicked relative lead you into danger (treats included).

Are there more specialists to be consulted on this topic?