By adding level up AP into INT. But you will be weaker. I think for BMs, you need to have quite a lot of base INT in order to MP wash and then later convert the additional MP into HP. Do a forum search for HP washing guides and you will also come across Shiyui's calculator. Fill that in and there's a section that will clearly tell you what to do. Example: Level 1 - 50 = Add all AP into INT Level 51 - 155 = MP wash by adding level up AP to MP and then using AP Resets to remove the MP and +Primary or +Secondary stats Level 156 = -INT and add back to +Primary or +Secondary stats Finally -MP and +HP until you reach your HP Goal Above is a very basic/brief of what I can recall from Shiyui's calculator with instructions.
You really do not have to HP-Wash anymore since quite a while now. Allthough if you get your All-Stat Gear such as a Zhelm, HTP, Dojo Belt, Ellin/Quest Medal and some event stuff like the rings that are you can get now or a Rudolph Nose during Xmas you can gain quite a decent amount of INT and therefor extra MP you can use to wash out some extra HP. There are many viable sources of gaining HP from (viable) gear such as Belt, BFC, MoN, Quest/Card Medal and Pet Equips. You can do Olaf's Assignment, Spring of Youth and daily HP Quests from Reuel in the alchemy place (magatia?) for more HP. If all of this doesn't appeal to you. I had spend about 6b on APR to get a BM to 9k hp and 9k mp at level 150. Wich doesn't include the price of getting a 200 INT BM to level 150. It's up to you if you rather burn that amount of meso before figuring out if you actually enjoy playing the class. If I were to do it again I'd make a MM :s.
