I honestly have no clue how to script, this was just an attempt. I am trying to change the width of a beam, this is my script.
while true do wait()
script.Parent.Width0 = math.random()*15
script.Parent.Width1 = math.random()*15
script.Parent.Transparency = NumberSequence.new(1,1)
script.Parent.Enabled = true
end

4 comments
is this a local, or server script? If it is a server script, i think the size is a vector value, not the way you did it.
The beam is always transparent, because of line 4. Does that ring any bells?
RAFA the transperancy thing has to do with something else it's just in the same line of code. The beam is viewable, I just want to randomly change it's width on startup.
^^ Actually, a transparency of 1 should make it invisible. You're able to replace the NumberSequence with simply the number 1.