Practically speaking, for the vast majority of us, finding a dream home is often quite a lot easier than actually affording it. You obviously want to get the best home possible, however it is probably not simply a case of what you need or want but what you can actually afford. So to begin, although you don't need to be an accountant, you will need a budget.
Start by working out the expenditure associated with the purchase. Remember that this is not just the initial mortgage deposit but one off costs such as the Stamp Duty, solicitors fees and removal costs.
Next, by reviewing ongoing income and expenditure, calculate what you can afford to repay. (CAN WE ADD A SIMPLE SPREADSHEET with some pre-populated fields) Be realistic; ensure that you can cover expenditure during the good times and the not so good ones times too. Find a balance, compromise when necessary.
With all the figures at your fingertips, work out what can you borrow and which lender will give you the best deal. Again the internet is a great source of information. When prepared, if you feel it necessary, proceed directly to lenders or speak to an independent financial adviser.