Choose the type of pickup you want to use. There are many styles of pickups. The most non-invasive pickup is one that slips inside your sound hole; these pickups have a chord with a 1/4-cable end that fits into an amplifier input jack. Under-the-saddle pickups are other options. These pickups do not change the look of the instrument, but they need to be installed into your instrument. Contact pickups are about the size of a quarter and are attached to the sound board and near the bridge on the inside or outside. Microphones that clip onto the sound hole are also available.
Install the pickup on your guitar. If you choose to put in an under-the-saddle pickup, or other pickup that requires drilling, allow a professional to install the pickup.
Choose an amplifier. Try out as many amplifiers as you can with your chosen pickup. Do not use an electric guitar or bass amplifier. Acoustic amplifiers are ideal for classical guitars. Alternatively, you can plug in straight through a PA system. Ultimately, you want whatever gives you the best tone.