Hi,
In order to help your friend they will need to make you a Super Neighbour so you can do their farms. Please see the following post on how to do that. If you are wanting to plow new fields for them, they will need to allow you to use their coins as plowing cost coins. Click this link and it will take you to the post
http://r1.slashkey.com/forum/showthr...26#post6024726