bald bloke:
The Rustler:
You might be allowed to sit in the cab … but I think most ASDA RDC’s still take your keys from you … if you want to keep your keys so that radio / elec. windows etc still work … get yourself an old set of keys … farm tractor / old truck … and hand those in … don’t give them your CAR keys … and then forget to get them back 
… not that I would ever do anything like this at ASDA 
If there’s wheel locks you can keep your keys and stay in the cab as your wheels are locked until the warehouse bods turn the light back to green for you then you’re good to carry on.
I used to go to Costco @ Magna Park … they had those wheel-lock bars … AND used to have to put suzie lock on AND hand your keys in AND sit in that stupid roof-less shed next to goods-in 
What you coming in with? Container will be on a bay, box possibly bay possibly under the canopy and pump truck it to the back to be forked off. Curtains under the canopy open curtains and side tip. If curtains or box under canopy no wheel locks just hang keys on the hook by the door.
Security are good and will point you in the right direction. Basically come in and follow round the building clockwise (its a one way system in and out) park up on the left opposite goods in ( you are allowed to go up by the canopy and screw it round to good side reverse it in, no need to bust yourself on a blindside) Hand in notes and sit in cab, forky or goods in guy will come out and tell you what bay when ready for you. If on a dock it will usually be 69 right next to the goods in door (70 and 71 are for us to tip reverse onto) Eggs are different, go to goods in, they will send you round to goods out to see the shunter who will give you a dock round that side. Dont forget to raise your trailer suspension if going on a dock . Get tipped and park back opposite goods in. Give it 15 mins ish and go in for your paperwork and off you go.
Got bags of space here, as others have said get it straight as you can and try to hug the offside, many a nearside mudguard has been torn off on the bananas because people get twitchy about being to close to the locking bars.
If you’re early enough I might see you, finish around half 8 9ish.
The Rustler:
Just take your time reversing onto the bay … go gently as your trl wheels go over the bar … if you look, you will see the bar come up between your trl wheels.
Just be aware … once you start to go over the bar … you get to a point where you then CAN NOT pull out to take another shunt … you need to be dead straight BEFORE you commit to the last few feet.
This might sound complicated … it ISN’T … once you see how it works, it will make sense.
If you look on You Tube … there might be video of how these bay locking bars work.
Our bars at didcot you can pull off and take as many shunts as you like, they dont lock until you push the red button
If you have a trailer with a rear steering axle it is a good idea to manually lock it before backing onto to wheel lock. I’ve known the wheel lock pull the rear wheel far enough out of alignment to make it (almost) impossible to pull the trailer off the bay when finished. Asda aren’t happy with you sitting on a bay for hours whilst waiting for someone to arrive then dismantle the system!!!
Cadburys Minworth have the same system. Which is rather pointless as they still make you disconnect and wait round the corner in a holding area. Still, at least you can go to sleep until the shunter comes round and wakes you up. Better than sitting in a smelly Tosco waiting room full of used coffee cups, a broken vending machine and a mouldy water cooler covered in legionnaires disease
Nothing to worry about, except mounting the yellow bars in front but with perseverence, you will get up there. 