The most important Tip of all is how to save your ships with space trip.
Only ships(any kind) can be put in space trip flight,defences stay on the planet permanently.
When this ships are in space trip they cant be destroyed in battle coz are flying around the planet from witch are send.
I recommend you to use this flight when you're not ON line in the game and save them. Please count the time when you will be off your PC/Phone and put them in this time.
Example: You have to go sleep 8 hours.
Click Fleets -> Select max(if you want all ships) -> Choose "space trip" -> Continue -> Select max LOAD(your resources will be load on the ships you send) -> Choose flight time 4 hours and 0 minutes(this time is the fleet go in one direction and when she reaches it-go back with the same time(4 hours) and you have 8 hours of space trip-> Click "Send Fleet"
The second reason to put them in space trip is when some one attack you and your fleet is not capable to win the battle fight between your(defender) and his(attacker) ships.