I have a bit of experience of this (used to do drawings for planning permission in my spare time) but I'm no expert & I'm not an architect or anything like that!
However, my dealing's with local planning offices was, generally, a positive experience as they are a fairly helpful bunch.
My best advice is to get a copy of your potential build area (OS plan) Your planning office should supply this for a small fee (£10.00 ish) You just need to supply an address/postcode.
Then plot, to scale, your new dwelling, showing as much information as you can, i.e, will it have a shared driveway, it's own driveway, boundaries with other properties, etc. You also need to note what type of property bungalow, house, no of bedrooms, etc.
You can then email this or just go to your local planning office & ask to see a planning officer. They will then offer advice as to the likelyhood of whether this might or might not get planning permission but this will only be an opinion.
Depending on what they say you can then go to the next stage either outline planning permission or full planning permission. Outline planning permission is the simplest/cheapest but even if you get this, you still need to apply again for full planning permission which could be refused!
Hope this helps