Choose a fast web host
Now that we know how to measure site speed, we should start by looking at probably the most important factor in increasing your Magento Store speed - your web host. Your host will have such a large impact on site speed that almost nothing could compensate for a slow web host.
Choose your host wisely, and avoid shared hosting if you are serious about your site. Shared hosting is generally much cheaper, ranging from $5 to $15 per month, but if you plan on running a successful site it's not worth it. If you plan on making any money or attracting large numbers of visitors, start by trying out some virtual private servers (VPS).
Hosting packages are typically available for a trial period, either 7 or 30 days. Trial hosts, compare speeds over a period of time, and select one that you can live with. You may even try multiple VPS services simultaneously.
Also beware of being locked into contracts. Most internet hosting companies will offer you a large discount if you sign up for a larger long-term package. Don't do that unless you're absolutely sure that you like the host and that your site will run quickly on it.
In summary, avoid shared hosting and be wary of long-term contracts. Even small sites may struggle to achieve their goals or growth whilst running on a slow server. Start by looking at virtual private servers, and then you can look at dedicated hosting down the line if you want to get a little bit faster and more professional.