Every accent has a particular posture which reflects the usual configuration of the articulators. Finding this posture help to lead the accent to accurate articulatory gestures without interrupting the improvisational flow of natural language.
Jaw lowered and in some cases protruded
Lips protruded and lax
Tongue root retracted/raised
Velum lowered = general nasality
Here are a few samples
GOAT ɡɐɤ̯̈ ʔ
The first element of this diphthong is realized further forward and lower than in RP. The second element can be quite unrounded. It can be useful to start by substituting the diphthong in MOUTH, and then relaxing back to a less extreme, centralized diphthong.
The extreme version of this sound would be [ɔɪ] . Start by thinking that sound but, as with the other diphthongs relax away from that extreme. The starting point of the diphthong is really closer to the /ɑ/ of “father”.
The first element of the diphthong is lowered and relaxed from [e] to [æ̽ ].
The first element of the diphthong is raised and often nasalized. The second element is unstressed or dropped.
TRAP ≠ BATH tɹæp bɑːf
All London accents make a distinction between two sets of vowels that in US English are generally pronounced the same: TRAP and BATH. Words in the BATH category are pronounced with [ɑː].
The vowel is first formed in a lax position, arriving at [i] after gliding through [ɪ] or[ə].
In the same way, the vowel is first formed in a lax position, arriving at [ ʉ ] after gliding through [ə]. In addition, the final element is considerably fronted.
In postvocalic positions after a vowel, /l/ is so loosely articulated as to almost become a vowel. This results from relaxation of the tongue tip away from the alveolar ridge, and an added articulation at the lip corners. You’ll notice, too, that this only happens when the /l/ isn’t followed by a vowel in the next word or syllable. In the word “really” below, the /l/ is pronounced as it would be before a vowel…because it is before a vowel.
/h/ is dropped, particularly in unstressed positions.
/θ/ can be realized as /f/, particularly in unstressed positions.
This, too, can occur in initial, medial, or final positions. In initial positions the sound can be lightened to the point of resembling /n/.
Glottal stops can replace /p/, /t/, and /k/ in medial or final positions.