Easy Fish Catch Trophy This trophy is obtained when you have caught your first fish. This is a simple trophy to get and can be done on any water with any species. Just cast out your float/lure/carp rod and hook and land one fish.
Easy Fully Hooked Trophy You get this trophy when you have caught 250 fish in total. You can catch 250 fish, of any species in any lake/canal and DLC fish count towards this total. If you have the Talon Fisheries DLC you will be able to grind this trophy quickly. If you do not have the DLC the best place to fish is Grand Union canal.
Easy Up And Comer Trophy This trophy is earned by catching 50 fish weighing over 25lbs. The fish you catch can be any species and DLC fish are included. Carp fishing on Gigantica is a good place to attempt this trophy as most carp there break the 25lb barrier. If you use a 4-8 hook, with 15/20mm boilies you will catch plenty of carp at a decent rate.
Easy Down And Outer Trophy You get this trophy when you have lost a total of 25 fish. It is a simple trophy to get and can be done by hooking a fish and then losing it 25 times. You can lose fish by having too much line tension, or letting them run free for too long. It's easier to lose a hooked fish if you 'poor strike' them on catch. Bass fishing or Predator fishing is the easiest way to get this trophy. You will however get this trophy naturally through the course of the game.

Fishing Sim World Trophy Guide
Easy Catching Carp Trophy You will get this trophy when you have caught a total of 200 Carp. You just need to catch a total of 200 carp of any species and can include DLC. The species of carp you can catch include Common, Leather, Mirror, Koi, Ghost, and Siamese and the fastest place to catch them if you have the DLC is Talon Fisheries in the Koi lake. If you do not have the DLC then Grand Union canal.
Easy Competitive Edge Trophy This trophy is obtained by catching 25 fish in one multiplayer session. The easiest way to get it is to select multiplayer from the menu where you can either join a session or create your own. Once you have caught 25 fish in that session you will get the trophy. If you join a session that is in progress you may not have enough time to complete the requirement for the trophy so unless you plan to fish in a lot of multiplayer sessions you are probably better off doing this in your own hosted session.
Easy Boast And Gloat Trophy To get this trophy you must win 25 multiplayer sessions. This can be easily done by going to multiplayer in the menu and opting to fish with friends in 4-player multiplayer. Set the time to 10 minutes which is the shortest amount of time you can play for. If you now just play that 25 times catching at least one fish each time the trophy will unlock.
Easy The Prospector Trophy You will get this trophy when you have earned 10 single-player gold medals in the offline tournament section (they do not have to be unique tournaments which makes it easier). Any of the base entry tournaments you will be able to get gold without trying. The easiest tournaments if you have the DLC are the Lough Kerr and Talon Fishery ones.