From Vigo the easiest way is to take the highway to Baiona and leave it in Baredo, from there take the PO-552 towards A Guarda along the coast. 12 km ahead, at km 29, there is a road on the left taking to Mougás and Viladesuso.
Drive 200m approximately and take to the right towards Viladesuso.
1km ahead before coming in Viladesuso there is a path on the left which takes you directly into the neighbourhood of Serraseca where Budiño is.
From A Guarda follow the PO-552 towards Baiona. 15km ahead, at the end of km30, almost at km29, take to the right towards Mougás and Viladesuso. From there follow the same instructions as if you were coming from Vigo.