Re DocHH's post:
I'd be wary of using any external agency, as they tend to charge you for doing what you can do yourself (and don't provide any additional benefits).
I based my post upon following links from the website of the Russian Embassy:
https://www.rusemb.org.uk/visa/
Assuming that you're seeking a tourist visa (rather than, say, a business one), that takes you here:
http://ru.vfsglobal.co.uk/tourist.html
(Clicking on 'How to Apply', and then on 'Biometric Submission', leads to the quote I provided above)