Fishing has been a part of the game for several years now, but until recently was predominantly a simple pastime, rather than an experience gaining exercise. Now, however, fishing offers a very efficient way to learning foraging and a reasonable way to learn animal lore. Furthermore, at lower ranks, fishing can also be a way of keeping mechanical lore moving.
A few things to keep in mind before you begin fishing:

• Empaths will get shock from it.
• You will probably need to spend some money to get going. Generally not more than a couple of gold.
• If you're a ranger, you may find that many fishing spots are in-city, such as docks.
• It's not a miracle way of learning foraging, but it does break the monotony of finding grass or sticks.

You will need a few basic things to get started. Generally, a pole, some line, some hooks and some bait. These items are generally sold at fishing supply stores near fishing spots. For instance, there's a fishing store at the south end of the docks in Aesry.
It would appears that the types of fishing poles, lines and hooks do not have a significant impact on the fishing experience, but the general rule of thumb seems to be to pick the hook and line size that is sold at the shop closest to your fishing spot. It has also been the said the larger the hook and line, the less likely that the big fish will break it. That having been said, going for the largest hook and line would probably not be a bad idea.
One thing that should be noted is that the bait types may have some impact on the fishing experience. In particular, live bait (such as worms, live fish and grasshoppers) are more difficult to put onto the hooks themselves, though with over 100 rank of mech, you should not miss too often. It's not entirely clear as to whether live bait actually generate more fish, but they do tend to be somewhat more expensive than their unliving counterparts, so there may be something to that.

Once you have your line (which will be in an envelope), your hooks (also in an envelope) and pole (which is collapsible and should fit in your backpack), you will need to assemble the tackle. First you will want to open my pole to expand the pole. You will then need to get line from envelope to attach your line to your pole. Then, with the next envelope, you will get hook from envelope to attach the hook to the end of the line. Each envelope is good for several uses, and you may find you will need to reattach line and hooks if you lose them. When you are done with this, you can close my pole to fold it up into a size suitable for travel.

Coming soon.

After you have your pole setup and have found your fishing spot, it's time to bait the hook and catch some fish. Out of the baits, the most effective should be the live ones, such as grasshoppers or worms. If your mech is fairly low, you may have better luck using the artificial lures, however. Once you've made your decision on bait type, you'll have a box that contains your purchase. With pole in hand, you will need to get <bait type> from my box which will attach the bait. Now you're ready to catch some fish.

At your fishing spot, cast my pole to start the fishing. Once the line and bait are in the water, you will need to wait for a fish to bite. The most common method for actually catching fish is to cast out, wait about ten seconds and then pull my pole to bring the line back in. You can also just wait for something to bite. Additionally you can look my pole to see the status of your pole, such as how far how out your bait is, whether it's baited, and so forth. Once a fish bites, you'll see some messaging like:

You feel a slight tug on your fishing pole.
You feel a hard tug on your fishing pole.
You feel a definite tug on your fishing pole.

At this point, you will need to rapidly pull my pole to haul the fish in. Once its landed, you can stow the fish, or otherwise stash it, lest it flop away from you. If you do not successfully manage to land it, you will see a message to the effect of Suddenly, your line goes slack! meaning that the fish is gone and your bait most likely is as well. Another possible message is Your fishing pole tugs downward a little, the line vibrating as the tip of your pole wiggles back and forth for a bit. which does not mean you have a fish on your line, but that there's a fish that will potentially bite at some point.

Fish weigh a lot. Once you have gotten a enough of a haul, you will notice that burden will be impacted and it will be time to sell the fish for some meager profit. You will want to find the fish buyer and ask him for some string which will give you hook and string, an item very similar to bundling rope, but used for combining fish. Before actually selling your fish, you may wish to take them to the fishing shop and get them weighed, to see if you have managed to get a prize winning fish. Once at the shop, you will put my <fish> on scale to have it weighed and the person will let you know the size and hand it back to you. Once your fish is weighed, you should have the hook and string in one hand and type put my <fish> on my string. The string tends to get heavy pretty quickly, so if you are intending to fish for long periods of time, getting several is handy. This string cannot be undone, so once a fish goes on, it is permanent. The string can also then be sold to the fish buyer that you originally got it from. give my string to buyer to sell it.