Let's be honest: time is not always a luxury in the world of show business. So if you need to faux-master an accent in minutes, this is the guide for you. Instead of getting caught up on every sound, let's cut to the chase so that you can get back to acting.
However, before you rush into learning an accent, it might be worth reading the post 'What's in my Mouth?' to get a handle on the sounds your mouth can make. Then follow my 4 easy steps for fool-proof accents ...
1. Where is the accent in my mouth? I find that this is the ultimate secret between sounding like a person doing an accent, and actually speaking in the accent. The Accent Kit is the best at exploring this idea, with their 'zones' ranging from 1 at the front of the mouth (an excellent spot for Irish, Welsh, or Standard British accents), 4 at the back of the mouth (giving a more American sound), and 7 in the nose (placing you square up in Manchester). Listen to find the zone of the accent, and then try speaking with your voice aimed in that area only. You'll find the sound changing, even if you aren't changing must else in your accent. Which brings me to ...
2. Find the hesitation sound. Think of all the times in speech you pause to think, letting out an 'uhm'. Or perhaps you prefer 'erm' or 'uh' or 'eh' or 'ah'. That is your hesitation sound, and it varies widely in accents. This sound can often be found through the 'zone', which we covered in #1. An accent that likes to hesitate on an 'eh' probably sits farther forward in the mouth than an accent preferring 'uh'. You can understand this idea better by reading 'What's in my Mouth?' Vowels 101.
3. Figure out 2-3 differences from your own accent. You're on a time crunch, so skip the phonetic analysis! Listen to the accent and think ok, what is extremely different sound-wise? Do they pronounce an 'r' when you usually usually do not? Or maybe they change their TH into Fs? Have a think, but don't bog yourself down. Go for the 2-3 most obvious changes and you're good to go.
4. When all else fails, anchor yourself in 1 sentence or phrase that you feel confident saying in the accent. When you're off track, come back to this phrase to help get your mouth and brain on the road again.
Picture from How to Do Accents by Edda Sharpe & Jane Haydn Rowles