On an excellent (but now closed) old topic (Powering servos and arduino), I learned a safe way of using one unique power supply to both power my servos and my Arduino.
Basically, the idea is to use a regulated power supply, with enough current (power), and a decoupling filter:
However, still a couple of questions remain:
1-Where in Arduino Uno should I connect the 5V? In Vin? Or perhaps in 5V port? Other?...
2-Where in Arduino Uno should I connect Gnd? In a Gnd? Any Gnd? Other?...