This is the advice i have been given from a very experienced friend of mine about the best way to develope your moon.
The first thing is to build a lunar base (obviously)
Then the sequence goes
Robotics1
R2
Lunar Base2
R3
R4
LB3
R5
R6
LB4
R7
R8
R9 (Optional)
Portal
This will bring down the build time of the portal to around 10 days, once this is done you deconstruct your robotics. The sequence is as follows
-R8
Sensor Phalanx 1
-R7
SP2
-R6
SP3
-R4
SP4
-R3
SP5
This is the best method to use. But there is a quicker way if you just want to spy on peoples fleets.
The sequence is
LB1
R1
R2
LB2
R3
R4
LB3
SP1
SP2
LB4
SP3
SP4
This takes about 1 week to do.