Gnostica is an immersive game, with many options available each turn. New players are frequently confused about what they should be focusing on during their turn.
Drawing and playing cards
Play several cards before drawing new cards, because drawing new cards costs a turn.
You can use a rod to push one of your pyramids into position for attack. You can also push one of the other player's pyramids (e.g. cooperating in an attack).
If you occupy a high-value territory, try to arrange a rod territory on the side away from the rest of the territory, with a two- or three-pip pyramid on it. That way anyone else trying to occupy the territory can be pushed off.
Moving a high-counting card away from the others and/or destroying territory connecting to the others make defense easier. However, it also makes offensive moves more difficult.