Professions are jobs you can complete on skyblock, the max level that provides rewards is 50, anything over this doesnt provide rewards and the experience you need to reach the next level increases the higher level you are. You get a minor stat boost and money each level you increase in any profession and special loot that can be crate keys or a random spawner.
You can obtain Random Profession Boosters from Monthly Crates. They will give you a booster for one of the five professions, all of them work global. It will double the amount of experience you and everyone else collects for that profession for the next 30 minutes.
Fishing experience can be gained by fishing, we have a plugin that adds a bunch of new fish and makes it so you have to hold right mouse button until you catch the fish. Each level you gain in this proficiency you get a + 0.05 addition to your maximum health and a small amount of money.
Smelting experience can be gained by smelting items in a furnace. Each item grants a different amount of smelting experience. For example smelting ores will give you more experience than smelting meat or wood. Smelting ores in a Blast Furnance and cooking meat in a Smoker will also increase your smelting experience even faster. Each level you gain in this profession gives you a + 0.10 addition to your armour strength, which protects your health more meaning you take less damage.
Woodcutting experience is gained by mining wood, wood minions do not provide experience towards this profession. Each level you gain in this profession gives you a + 0.03 addition to health regeneration which increases how fast you recover hearts.
Slayer experience is gained by killing the custom mobs and bosses in any three of the mines. Each level you gain in this profession gives you a + 0.10 addition to your critical damage.
Farming experience is gained by mining carrots, potatos, wheat, sugar cane, pumpkin, melon, cactus, mushrooms, netherwart and beetroot. Each level you gain in this profession gives you a + 0.05 addition to your max health.