1. Auctions. But you need to know what you are doing, at least a bit - make sure you thoroughly understand the legal pack, have a structural survey and are familiar with what is happening in the neighbourhood before you bid. For a beginner's look at this, try Homes Under the Hammer on BBC iPlayer.
2. Look around for neglected/vacant properties and plots in your area, research who they belong to (Land Registry, neighbours, electoral register, etc) and make an offer.
3. If property in your immediate neighbourhood is too expensive, there is probably somewhere else in the country which is cheaper and where you can buy a rental/potential retirement home while you live, work and rent in a more expensive area. But do be aware that long-distance property management can be a pain, and also see above advice about thoroughly knowing the area in which you are buying.
If you want to make money in property, you can 1) Self-build, 2) Renovate/extend to add value, or 3) buy and hold in an appreciating market, while either living in the property or renting out. On the financial side, you can use the time before you buy to put together a 20% deposit and to make sure that you have good credit scores and can demonstrate that you have income to spare for repayments on a mortgage - lenders will check your usual expenses against income.
