These guys are surprisingly easy to deal with 1 on 1 early game for me. I say early game as in when you’re still hanging out on the beach. I don't know how helpful this will be because I play on easier settings but...
1) Avoid them until you have cloth armor and/or a spear.
2) If somehow thats hard for you, try running away. Dont let them spit on you, obviously.
3) If you do want to fight them, all you’ve gotta do is keep your eyes on their animations, stay within melee range, and just keep stabbing them until they die. If you avoid the initial attack then they should be easy to kill.
Again, I play on easier settings as a casual player so I don't know how accurate this will be for harder difficulties. I am also assuming the Dilophosuarus are low leveled.
They make a distinct aggro sound when they lock onto you, keep this in mind when one is nearby. They are easily outrun and with very little practice you can avoid their arcing acid attack. Spears/arrows to he head are very effective
Ever seen Jurassic Park? If not be aware, to the average new player they seem like an easy hunt. But do not let their small size fool you. These creatures can hurt even high level players. If you have to fight one try jumping around a lot to avoid getting blinded. Good luck!