What is Fleetsaving?
Also known as Fleet and Resource Saving or FRS, is a proactive action to protect your resources and ships when you are not actively using either.
No Fleetsave = No Fleet

Why bother to FRS?
All active players are at risk of attack. If your ships or resources are sitting on your planet they are a target and if you do not protect them while you are away, you will lose them REGARDLESS of the amount of defenses you build.
No Fleetsave = No Fleet
Example, planets ‘protected’ by 39 Zeus have been raided as have immensely well ground defended planets (ie, 300+ plasma etc)

How do I Fleetsave?
That depends on what you have available:
New to the game:

    You’ve just started; have no ships and limited resources. Build mines with solar arrays to power them and/or research. Buildings and Research (unlike defenses) can not be destroyed or taken away.

Look Ma’ I got ships:
Your fleet is growing but Dionysus Class Recycler is still locked (Shipyard 4 – Jet Drive 6 – Shield 6). To protect your ships send them on a slow attack mission:

    • Find an inactive target. These can be found in the galaxy view with either (i) or (I) in orange next to the player’s name. * there may be other letters in the parenthesis, such as ‘n’, ‘N’, ‘d’ or combinations such as (idn), if it contains ‘v’ or ‘s’ you will not be able to attack
    • Probe the target. Important so you do not encounter unexpected defenses (all defenses are automated, so even if a player is inactive all planetary defenses will work).
    • Adjust the speed of your attack to half the time amount of time you will be away from your computer. Attack time is only the amount of time to the target, not total flight time. Example: If you are going to be out for 8 hrs, slow down your fleet by adjusting the percentage of speed you fleet travels to 4 hours. Your fleet will travel 4hours to the target and 4 hours back to your planet. * a few minutes too long and waiting for your fleet to return is better than coming back to a debris field.
    • Enjoy the spoils of your attack and safely returned ships

These methods can be oracled (watched by a moon) and Oracle lock is possible, where an attacker will time the attack to land a split second after your fleet returns home.

Dionysus Unlocked!!
With the Dio unlocked Fleetsaving just got easier and safer. With at least 1 dio in your fleet you can send the entire fleet on a harvest mission. If there is a debris field around you can target that, any galaxy position (planet or empty planet slot), or a planet that you think may be attacked (sometimes you get lucky and can harvest a debris field)

• Go to Fleets menu
• Select the fleet to save, be sure at least 1 dios is included, or click select all.
• From the bottom of the fleet page choose Harvest
• Adjust the speed (percentage) and target of your harvest to half the time amount of time you will be away from your computer. Travel time is only the amount of time to the target, not total flight time. Example: If you are going to be out for 8 hrs, slow down your fleet by adjusting the percentage of speed you fleet travels for 4 hours. Your fleet will travel for 4 hours to the target and 4 hours back to your planet.
• Add resources to your fleet. Type in the amount of resources in the box or click MAX.
• Do this for every planet.

Harvest missions con not be tracked by and Oracle.
This is the reason this is the only way to fleetsave as soon as the dio is unlocked.
Be sure to make your fleet return after your online, better to wait 10minutes than have no fleet when you return.

No FRS = No Fleet

Tips
• If you find you have too many resources to completely resource save them all, then start of a slow building project or research project that will finish when your back online, this way you can hide the resources and simply click cancel when you return.
• At higher ranks be sure to vary your fleetsave times, certain hardcore players may spend weeks watching for patterns in your fleetsaves and try to land between your fleetsave landing and when they think your actually online.
Always have your fleet land after your online, better to wait 10minutes than have no fleet when you return.
• You can leave a batch of probes behind when you fleetsave, that way while you wait for your fleetsave to return you can start to probe for targets.

Ways You Must Not Fleetsave
Even if you suddenly think ‘ooo a new way to fleetsave more cheaply or easily’, take it from those who know, the methods below do not work.
• Trading, fleetsaving by initiating a trade and leaving it pending does not work, if you are probed the pending trade will show on the report, if you are then attacked then the trade is cancelled and the battle occurs as normal.
• Slow attacks, not only are slow attacks classed as harassment, they are also trackable by Oracle users and your fleet will likely be destroyed on it’s return.
• Colonisation, you cannot colonise a planet currently occupied.

more info at: http://wiki.playstarfleet.com/index.php/Fleet_saving

No Fleetsave = No Fleet