[Samoht]

First, set forage to one of the buttons 1 through 6 on your abilities tab.

Make a macro that does /doability # where # correlates to the number from the tab.

You will need a /pause to wait for the pickup to resolve. /pause works in tenths of a seconds, so /pause 10 is wait one second. It can be on the same line so it looks like this:
/pause 10, /doability #

Even though the pause is logically listed first, it resolves after the action on the line. So this will doability forage and then pause 1 second.

Finally, you use /autoinventory to drop your foraged items into your inventory. What this does is basically emulate clicking the blank space in the middle of your inventory screen.

Now you have this:
/pause 10, /doability #
/autoinventory

But wait, there's more! You can only forage while standing, so why not build a /stand (while it works) or /sitoff in the macro? And use a pause!
/pause 5, /stand
/pause 5, /doability #
/autoinventory

Not finished yet? There are five lines available on a basic macro, so you can add more stuff to it like sense heading or track, too.
/pause 5, /stand
/pause 5, /doability #forage
/pause 5,/autoinventory
/pause 5, /doability #track
/doability #senseheading

And then if that's not good enough, you can map that macro to a direction key on your keyboard so that every time you turn right or turn left it goes off. The only thing to be mindful of is if you already have something on your cursor, forage will fail to activate, so you can work in an autoinventory at the beginning as well.

/pause 5, /autoinventory
/pause 5, /stand
/pause 5, /doability #forage
/pause 5, /autoinventory
/doability #senseheading

Be mindful that if you're holding something or doing a tradeskill, this will cause you to drop whatever is already on your cursor, so don't hit it unless you already have an open cursor or open inventory space. /autoinventory will force you to drop whatever you're holding if there's not an open space.