Surfing Waves

I'm going to Nicaragua and I need to get a board bag. I don't have the money for a typical travel bag. I was thinking of getting a day bag and getting foam padding and wrapping the rails and the board with it. Has anyone ever used a day bag for the airlines? If I wrap it with foam and bubble wrap will it be cool?

A day bag will if you do what you are suggesting. Customs like ripping through bubble wrap so your bag may not survive its first inspection or will need running repairs. Hope you have removable fins, they are a failure point in the football match your board is going to. Pipe lagging the neoprene foam type is good around the nose and tail.
I have seen boards travel safely without any serious cover and I've seen boards destroyed in full travel bags.
Are you really traveling but can't afford a travel bag? I seriously hope you have taken out proper travel insurance!