19:52 Nov 22, 2011 

The 4 suggestions (so far) are all "British" English, but the decision now depends on level of formality/informality, age group, and of course, the rest of the document (if there is a document)

12:13 Nov 22, 2011 

are all great; the deciding factor will be just how informal your context is (whether slangy expressions are acceptable/required) and whether, as others have commented, it is particularly youth-oriented.

10:06 Nov 22, 2011 

Charles, perfectly put.... BTW I have no problem with my age!!

09:57 Nov 22, 2011 

Hi Sarita. If I may, I'd like to say that both the suggestions so far, "grab some kip" and "get some shut-eye", are absolutely authentic British expressions. Both are colloquial; the difference, I'd say, is that "grab some kip" is more likely to be said by a younger person and "get some shut-eye" by someone of more mature years (such as myself or Andrew, judging by his photo: no offence, Andrew!). There is arguably an element of social class in this too; "shut-eye" is somewhat more genteel than "kip", which is slang.

09:53 Nov 22, 2011 

Hi, sorry for lack of context. Yes I do mean an idiomatic UK English expression for getting some sleep, thanks.