You are more likely to hear the characteristic call of a Chiffchaff before you see one. These tiny leaf warblers, which are one of the first warbler migrants to arrive in the UK and for me herald in the start of spring, are normally spotted energetically flitting high through the leafless trees. The only time they stop moving is to go in to their characteristic two note song.
The main challenge in terms of their photography is trying to find a bird that is a bit atypical and not too high up in a tree and using low bush or trees to forage and sing from. Like many warblers once they have established their territory they will often use the same set of song perches to sing from to attract a mate. Like the bird's appearance, the song is not the most exciting and sounds exactly like their name. However, it conveys the apparent unstoppable energy of the birds and often is sung relentlessly for very prolonged periods.