How can I make a script which specifiys all Players in a game and for example give them sparkles?

So, I've been trying to make a script which simply affects all players Ive tried localplayer and so forth but does not seem to be working can someone please tell me another way?

Well, you would need to access all players at once, so you'd use something like this

for i, player in ipairs(game.Players:GetPlayers()) do

end	

That accesses all the players.

If you were putting sparkles, then you would put a sparkle object in replicatedstorage for example, and clone().parent it to the players character.

so you would implement this like so

repstorage = game.ReplicatedStorage
sparkle = repstorage.Sparkles

for i, player in ipairs(game.Players:GetPlayers()) do
		if player.Character then
			sparkle:Clone().Parent = player.Character
		end
	end	

that adds sparkles to all characters.

So you can modify that code for whatever you need.