Simple Cell Value +1 macro

Hello,

I'm trying to write a basic macro which will increase the value in a cell by 1 when I click on the button I've made. I've searched for hours on the Internet, including this site, and found several websites which give a formula needed but none of them work, I always get an "Object variable not set" error or something about sub-functions which I can't recreate so I can't give the full error message. Sorry.

Based on what I've seen on the Internet, I currently have:

 REM  *****  BASIC  *****

Sub WebsitePlus
ActiveSheet.Range("B18") = ActiveSheet.Range("B18") + 1
End Sub

Where B18 is the cell which currently says 0 and I want to go up by one every time I click the button.

In this macro, the B18 and the 1 are highlighted in red, presumably meaning they're the bits that are wrong. I get a "Basic runtime error: Object variable not set" error when I run it.

Thanks in advance for any help.