Projectile_Misfired, on Jan 19 2023 - 11:48, said:
One thing that I wish I knew when first playing arty is that you can use the "Shift" key to go into "God-view". So, there's your first tip.
I agree and please allow me to further elucidate on the use of the Shift key.
What one does is tap the SHIFT key to go into the overhead view. Tap again to leave.
I mention this because some SPG beginners (cough cough) initially make the mistake of trying to hold the Shift key down. 
Also, while in overhead view, tap the g key to enter Trajectory view and tap g again to return to overhead view. The g key does nothing if you're not already in the overhead view.
BUT! If you are in Trajectory mode and tap SHIFT to return to normal view, the next time you tap SHIFT you'll go straight into trajectory view.
And here is a bonus tip: While in overhead or trajectory view and want to check out a potential target, press and hold the left CTRL key and right click on the target on the minimap. You'll immediately see whether you have a line of fire or not without having to move your gun. Let go of the CTRL key to proceed to target, or keep holding CTRL and right-click and check other potential targets.