Want to make your home secure against burglary? Thinking of fitting your own burglar alarm? Here are some guidelines from a professional:

[edit] Steps

Look at your boundaries. Can you improve your fences or hedges and gates? Examine your doors and windows, including basement hatches and the like. These should be made reasonably secure before you even start with electronic security.
Identify what you want to protect. This will be:
- You(and your family).
- Items of personal value(e.g. jewellery or collections not easily replaced by insurance)
- Your home.
Plan your burglar alarm system. Use the minimum number of sensors to cover strategic areas of your home - for example hallways and corridors. The fewer sensors you use, the less chance of a false alarm. False alarms should be avoided at all costs.
Speaking of costs, use the best sensors you can find. One good sensor is better than 10 cheap sensors. You will be able to rely on it.
Use a loud sounder outside and a loud sounder inside.
Use a good quality control unit with a stand-by battery. The battery is very important as it will stabilise the power supply, making the system more reliable. Replace batteries regularly.

[edit] Tips

Keep it simple. There is little point in having an elaborate system connected to a security company if their response time is going to be too long.
Make it noisy. Contrary to what you see in the movies, intruders can not easily defeat alarm systems - especially on relatively low reward risks. They will not stay long if they think they will be disturbed.
Get advice from local specialists. Every neighbourhood has a different crime profile.

Never tackle an intruder. Their wish to escape will override your wish to stop them and you will always come off worst. They will probably be armed, even if it is only the tool they used to effect entry.
Don't try to install your own system unless you have a reasonable degree of experience in electronics and electrical installation. It isn't worth the false alarm hassle.