For those of you who haven't taken the time to just look up what it is on the wiki I'll just give you a quick synopsis. An interdictor is a Tech II destroyer that is capable of fitting an interdiction sphere launcher and using it in Null Security Space to launch warp disruption bubbles. If you want more than that go read the wiki page. The purpose of this page is to tell you how to fly the damn thing.
1.) DON'T BUBBLE YOUR OWN FLEET (Unless FC says so)
a.) This is the number one rule on fleets. Just don't be that guy. You will get primaried...
2.) You are flying a glass cannon - Treat it as such
a.) You are expensive, a big threat, and easily destroyed.
3.) Don't sacrifice your ship unless it's necessary.
a.) An interdictor is one of the most utilitarian ships in a fleet. Try not to make yourself useless...
When I was a newbie, the job of interdictors was stated to be tackling the enemy fleet, right? And dictors are universally accepted to be expendable. So of course as a newbie I put the two of these together, and imagined a fleet on fleet battle where I fly into the middle of the enemy fleet, trap them in a bubble, and they all die.
This pretty much never happens. You're a destroyer, not tanky in the slightest, and a big threat. Of course you just die if you try to do that. First, it's rare to annihilate an entire enemy fleet. More commonly, you pick off a number of them until they decide they no longer like the fight, and then maybe you catch a few stragglers in addition to what you've already killed. Dictor piloting is much more about predicting and preventing their *next* move than anything else. You'll almost never be able to fly from your fleet to an enemy fleet.
A more likely way to execute tackling an enemy fleet in battle has much more to do with preparation and prediction. It would likely involve warping between celestials to get into a position that's on grid with the enemy, very far from them, and in the direction they're aligning. You would need to predict that moment when the enemy FC will be ready to get out of the fight. Then you'd warp to a wreck at some distance, probably 100km, and bubble in front of them as they approach you.
Generally more common and more useful than actually tackling, however, is just slowing and stalling the enemy fleet. Done well, this can drastically swing a battle in your favor, and is *extremely* annoying to the enemy fleet. A great example of this is the battle between TEST/Legacy and CO2 in XWY-YM. CO2 expected to have Triumvarate help them in that battle. However, due to poor planing by Tri, and an excellent job by Farmstink's small squad of interdictors, Tri was never able to make it to the battle.
First, read a map. The intel map is excellent for this. Dotlan works as well. You need to know the direction the enemies will be coming from and their likely destination. You'll generally want to be set up several systems ahead of them, and you may want to make bookmarks in several systems before they arrive.
Minimum warp distance is 150km. Use this to your advantage. A stop bubble place 100km from the gate is significantly more effective than one place 160km out. The pilots can't simply fly out of the bubble and warp to the gate; they must warp to another ping or slowboat the 100km. This will likely require you to make bookmarks ahead of time. I enter the system from the same direction I expect the enemies to come from, reapproach the gate until I get near 0, then warp to the outgate at 100km and set a bookmark. Once you're there, you can optionally fly directly back to the gate you came from and set another bookmark. You can potentially use this to sit 100km off the in gate, put a bubble up when enemies enter local, and then warp to your outgate bookmark and bubble there as well. You can use the extra time you bought to get to the outgate at 0 and wait. Depending on the situation, you may be able to watch the enemy fleet warp into your new bubble or warp to your ping, and then bubble 20km out in the direction of their new ping. I say 20km because you want the bubble to be far away from the gate to be effective, but you also want to have time to get back through the gate before you're killed. Depending on fleet comp, you may be able to stall a fleet for 3-5 minutes in a single system, and then you can repeat in the next system.
Another situation where dictors are required is to tackle an enemy cap fleet. You absolutely will lose dictors doing this, and many dictors may be called for to do the job. It's very important that dictors are organized. Preferably there would be an assigned dictor FC, but this isn't always the case. These are the kinds of details that are extemely helpful, but the main FC often doesn't have time to address them all. It's on the dictors to organize themselves in this case. Find someone experienced, and if you can't, do it yourself. FCs have a tendency to call for “all dictors do X” when that has a reasonably chance of blowing your entire dictor wad at once. Usually you just need one or two dudes to do it, but you need to MAKE SURE it gets done, so the FC just calls for every dictor to suicide. Make both a chatroom and a mumble subchannel for dictors only. When a call like this comes, ask two dictor pilots to X up. The two that X up are the first to go in. Tell the next two that they're on deck. Especially for things like keeping supers tackled, you generally only want a couple active dictors at a time and the rest should remain in reserve. This works better if you anticipate the FC calling for stuff like this.
Disclaimer: Follow Orders. But try to understand the intent behind them, especially for interdictors. “Bubble up on land” is a good example. You have to know what they mean which is to catch the hostiles if you can. Don't bubble blindly when they warp off and your fleet is 3 seconds late. You just end up bubbling your own fleet that way. All dictors bubble that guy usually means that dictors should have a channel and 2 or 3 should X up and go. See the “Tackling many caps” section. FCs usually don't have time to micromanage dictors. Experience and common sense goes a long way in dictor piloting. You have to read your own map, have an idea of what your fleet wants to do and what the enemy fleet wants to do.