Can you pay kicker costs with mana from any source or does it have to match the kicker symbol?

Kicker is an optional additional cost you may pay when casting a spell (CR 702.33a). The kicker cost is written as a mana symbol or other cost, and you must pay exactly that cost if you choose to kick the spell — but the mana itself can come from any legal mana source, just like paying a spell's normal mana cost.

Normal mana payment rules (CR 202.2, 107.4) govern how you satisfy colored and generic mana symbols. If the kicker cost is {G}, you need one green mana — but that green mana can come from a Forest, a Birds of Paradise, a Llanowar Elves, or any other source that produces green mana. There is no restriction tying kicker payment to a specific source.

If the kicker cost includes generic mana (e.g., {2}), that can be paid with mana of any color or colorless mana, again from any source. If it includes colored symbols, those specific colors must be paid, but still from any source that produces them.

Example: You cast Territorial Allosaurus with its kicker cost of {2}{G}. You can pay the {2} with two red mana from a Mountain and a Savage Lands, and the {G} with a Llanowar Elves activation — no single source is required, and the game only checks that the correct mana types were spent.

So in summary: kicker costs obey the exact same mana-payment rules as any other cost. Match the symbols required, but draw from whatever sources you have available (CR 702.33b, 601.2f).