The first thing IT support suggest is unplugging and restarting your modem (the box connecting your home to the Internet) and router (the box that gives you Wi-Fi). In some cases the modem has a built-in router.
Microwaves, baby monitors, and cordless phones can all interfere with your Wi-Fi. Unplug any devices you don't use. Your neighbor's service might also slow down your connection. Check your router's setting to make sure it looks for the least-crowded channels.
Look on the bottom of your router. It should have a 802.11n or 802.11ac standard (for Wi-Fi compatability). If not, upgrade or update the firmware (built-in software).
Wi-Fi is like real estate: Location is everything. For best coverage, put your router in a central location. Avoid brick or concrete walls.
If you have buffering or dead spots (areas where Wi-Fi is weak) consider a Wi-Fi booster.