To install the HP Deskjet 3755 printer, start by unboxing it and removing all protective materials. Plug in the power cord, turn on the printer, and install the ink cartridges. Load paper into the input tray. Next, visit 123.hp.com/setup deskjet 3755 to download and install the latest drivers and software. Follow the on-screen instructions to connect the printer to Wi-Fi or use a USB cable for a wired setup. Once the installation is complete, print a test page to confirm functionality. Your HP Deskjet 3755 is now ready for printing, scanning, and copying tasks efficiently.