I picked up EotE as something new to play, right now i'm running the adventure modules to help everyone get familiar with the system as a whole.

What i'm wondering is if anybody can give some tips on building a complete custom game?

That's an incredibly broad question. What are you looking to customize?

I liked my approach, here is your ship, you are in space after just repairing the hyperdrive from a faulty conduit when you acquired the ship, what do you do?

Let them build the game, you build the events that are caused by their actions.

They decide to attack some freighter for cargo, you make that freighters company go after them

They deliver supplies to a colony on some backwater planet, the local pirates and perhaps Hutt wants word with them.

You let the world and story react and build from what they do.

A good plot hook is what you need, and it is especially good if it gives your party a reason to stay together. You can start some people off knowing each other, be it a guy and his droid or a couple crew members, but most of the time I think you end up with lots of different characters from different walks of life. If you get a good reason for them to stay together for a bit you are gold.

For building a whole custom game, you need a good plot hook with some memorable NPCs that the players would want to interact with, and perhaps a rival who keeps causing trouble. It really depends on what kind of campaign you want to run. Largely the NPCs and setting are what you need to focus on I think, and how they interact with one another and what their goals are.

Something I was thinking about doing is after a couple sessions either throw a young Jedi running from the Empire while trying to complete a pilgrimmage, the whole time being pursued and asking for assistance.

Or getting them looped into the Rebellion in some way.

Ask them what kind of campaign they're interested in playing in.

That said, in the last 25 hours, I've started tossing around ideas for a campaign in which the Tapani sector is engaged in full scale Game of Thrones-style manipulation, backstabbing, and all out war for control of the sector, with the PCs caught in the middle.

50 minutes ago, Gunnolff said:

Something I was thinking about doing is after a couple sessions either throw a young Jedi running from the Empire while trying to complete a pilgrimmage, the whole time being pursued and asking for assistance.

Or getting them looped into the Rebellion in some way.

This guy has some great tips for running sandbox-style games. Main takeaway, for me, is to know the basics of the story: "someone wants something really badly and is having a hard time getting it." Everything else is just filler, and can change as necessary

Start EotE campaigns with a simple job. I would recommend that it:

a. Lets them drastically alter the rest of the campaign based on how well they do/what they choose.

b. Is difficult enough to make the group seem necessary.

c. Highlights everyone's abilities.

d. Introduces NPCs that you like, especially a main villain.

e. Incorporates something (or someone) related to obligation.

I am currently running my first campaign and I started with the 2 adventures "Escape from Mos Shuuta" and "Long arm of the Hutt" to get both, me and the players, familiar with the system.

I also made a mind map with adventure ideas, plot hooks and evil bosses to organize some ideas.

In the game I gave out some information, some via a bulletin board, some via Teemos computers. Some of them lead to smaller jobs like bounties or cargo haul jobs, some smuggling, but some trigger new adventures, like "Beyond the rim", "Crates of Krayts" (in which I also incorporated the backstory of a PC, who is searching for his slave sister. She was sold by Teemo to Sinasu the Hutt, playing a role in Crates of Krayts), "Jewel of Yavin" (where my force user will get a chance to get her first lightsaber crystal) or "Mask of the pirate queen".

If this works well I will seed out some more info in these adventures, to start even more pre-made adventures or own ideas / plot hooks.

TL;DR:

Make a mind map with all your ideas and connect them to a campaign, but maybe start with some pre-made stuff to get used to the system. You can always include your own ideas or change to a fully homebrew campaign while your campaign runs

I think your best bet in this system is to not plan extensively. Design plot threads, not plots. If you let them, obligations will steer your story pretty heavily anyway, they make coming up with future story beats pretty easy.