If you are setting up your system for the first time then you have following options :
(1) Purchase a professional high gain antenna like Flightaware’s from Amazon.com, or Jetvision’s from jetvision.de .
(2) Purchase a low cost low gain MaxRad groundplane (Spider), and trim its elements as described in this thread.
(3) Make a DIY groundplane (Spider or Cantenna). See instructions here Three Easy DIY Antennas for Beginners
(4) Make a DIY high gain collinear antenna (Coaxial Collinear, Wire Collinear, Franklin Collinear). This is not recommended for beginners as most end up with a collinear which is worst than groundplane. You may try your luck with collinears once your system is up & running with easy & reliable groundplanes. The reason is that collinears are highly intollerant to dimensional inaccuracies caused by FLAWED DESIGN or INACCURATE CONSTRUCTION, and need test equipment to tune, which most diy makers lack.
If the length of coax cable between antenna & receiver is more than 5 meters / 15 feet, adding an amplifier becomes necessary, and boosts plane count & maximum range. Even with short coax length, amplifier does improve the plane count & maximu range. Due to high gain of amplifier, it is worth trying lower gain settings of the reciever dvb-t, say 45 instead of max or -10.