If there was an important battle – he showed up. If there were refugees – he took them in. If you needed a lift near the sea, and the Eagles were busy, Círdan was there. He didn’t lose sight of who the enemy was. If there was drama an in-fighting – he wasn’t there. If there was great power that someone else could use more effectively – he gave it freely.
Stand back, I have examples and quotes.
Fought long against Morgoth before the Noldor arrived
“Thingol was cut off from Círdan at Eglarest.”(The Silmarillion – Of the Sindar)
“And when Thingol came again to Menegroth he learned that the orc host in the west was victorious, and had driven Círdan to the rim of the sea.” (The Silmarillion – Of the Sindar)
Showed up to the Mereth Aderthad
“And there came also great numbers of the Grey-elves, wanderers of the woods of Beleriand and folk of the Havens, with Círdan their lord.” (The Silmarillion – Of the Return of the Noldor)
Kept up good relations with the Noldor
“Between Círdan and Finrod there was friendship and alliance, and with the aid of the Noldor the Havens of Brithombar and Eglarest were built anew…with the aid of the Elves of the Havens, some of the folk of Nargothrond built new ships…” (The Silmarillion – Of Beleriand and its Realms)
Also kept up good diplomatic and economic relations with Doriath
“These [pearls] Círdan gave to him, for they were got in great number in the shallow waters about the Isle of Balar.” (Unfinished Tales – Of Tuor and his Coming to Gondolin)