The Perseids remain a favourite with most observers.
Although they are out-performed by December's Geminids in terms of observed meteor rates, the Perseids have the advantage of occurring at a time of year when the nights are not too cool and at a time when many people take their summer breaks.
Perseid activity can be seen during the final fortnight of July and the first three weeks of August, but the best rates occur for a few days around Aug 12th. Perseid maximum in 2015 is actually predicted for Aug 13d06h UT and so the best observed rates are likely to be seen late in the night of Aug 12-13. However good rates are also likely during the nights of Aug 10-11, 11-12 and 13-14, so don't just focus on the night of Aug 12-13 (and risk it being clouded out).
Observations of the early Perseids in late July and the first week of August will face minimal moonlight issues - Full Moon occurs on July 31 - and, for observers at the altitude of the UK, the Moon will only move out of the evening sky over the week that follows. Indeed, on the night of Last Quarter, Aug 6-7, the Moon will still be rising before 23hUT. What makes things worse is that during this period the Moon is also moving closer to the Perseid radiant and is located in southern Aries at Last Quarter
Fortunately, observing conditions improve more rapidly after the Moon has passed beyond Last Quarter and it then diminishes in brightness and moves quickly out of the night sky. On Perseid maximum night, Aug 12-13, the Moon will not rise until morning twilight is well underway. New Moon occurs on Aug 14th
The Perseid radiant is circumpolar from the UK, so you should start to see some Perseids as soon as it gets dark. The best observed rates are likely to occur in late in the night when the radiant is higher in the sky.
Few Perseids will be seen if you look directly at the shower radiant (their paths will be too short to easily see against the star background). For the best observed rates, look at any area of sky around 20-30 degrees from the radiant and at an altitude of around 50 degrees (but obviously tailor this to take into account local factors such as sky obstructions and light pollution ... and of course the Moon)
Being rich in bright meteors makes the Perseid shower a good target for imaging.
Here are very useful guides to
imaging using a DSLR http://popastro.com/meteor/observingmeteors/DSLR/index.php
and imaging using a video camera http://popastro.com/meteor/observingmeteors/video/index.php
The shower is also good for trained meteors, with around a third leaving persistent trains.
Care should be taken to identify the correct location for the Perseid radiant (see the chart below) before observing, as this changes significantly between late July and the peak.