Farnham elected to play into the wind in the first half and received the kick-off.
The maul was set up well with Farnham charging towards the line. Harrison Horner was held metres short but Jonny Vincent was quick to pick and go to dot down for the first try of the game.
A well-executed lineout move then saw Toby Salmon break down the right before offloading to Joe Brockman, who was brought down just outside the 22. The ball was moved to the other side where Max Williams found Joe Wigmore and Wigmore beat the cover defence to finish off a brilliant score.
Tottonians scored their first try of the afternoon when they won a five-metre scrum and their number eight powered over in the corner.
Farnham suffered a blow when Williams was given a yellow card for a deliberate knock on.
Tottonians made their man advantage pay and broke through the middle to score their second try.
The visitors saw out the remainder of the half and led 14-12 at half-time.
Farnham had the perfect start to the second half when Wigmore pounced on a loose ball and sprinted in from 50 metres for his 15th try of the season.
The visitors scored their fourth try when the ball moved wide through Ollie Brown and Salmon, and Salmon found Reece Stennett who finished off brilliantly in the right-hand corner for the bonus point try.
Salmon added a penalty to the scoreboard to seal Farnham’s win.
By Toby Salmon