This depends upon the tile thickness and porosity...Basicly you apply a first coat of linseed oil mixed with white spirit...this will soak in quickly...apply subsequent coats neat until the tiles will not absorb any more oil...do not let any residue dry on the surface..
The linseed oil dries by oxidisation and dries hard.. this will enchance the colour.. The Oil alone isn't enough as a sealer , so then a product like Bri-wax is used to give it a final finish and upto 4 coats of this will be required.
All instructions should be on the products..
Also be careful with the rags from the Linseed oil...As it is dried it oxidises and this creates heat and the rags can combust.. so wash them out or dispose of safely...
Hi dave
Cheers for that very informative not got the linseed oil yet .new product to me on the terracotta.so i can advise the customer the right way has he is fitting it himself
I'd just double up on Daves note of warning re used rags combusting - it does happen - make sure you deal with them properly at time of use, not just left screwed up in a corner for the end of the job!
Dont let that put you off using the oil though - only proper way to treat terracotta. Good luck.