Tipping is very important in Egypt, as the vast majority of Egyptians are receiving insufficient wages that are sometimes inhumane. Therefore it's logic why they would depend on such money.

As being a tourist, you should consider regular tipping, because people expect it from you.

5 pounds tipping to low paid workers would make them grateful to you

One or two pounds are good tipping for bellboys, doormen, chambermaids, concierges, ushers, and other similar jobs.
For tipping your tour guide or a tour leader -if you are among a group- 10 pounds from each person is good enough.

You must take care not to underestimate tips for some individuals, as some might consider it insulting if you paid a far lower amount that they usually get.

Finally, it's better for you to get some big change, usually from the bank, before you embark on your trip.