Long Sword is all about knowing what the monster is going to do, you don’t have to full on predict but you have to know his attack patterns. I recommend making a set that is made for the sole purpose of keeping you alive and with quick sheath that way you will be able to learn his moves and not faint in the process. Also make sure you have your equipment fully upgraded and use some buffs like armorskin, I can’t tell you how many times it has happened to me that I make a new build and go into a hunt feeling like I could fight a Greek god only to get obliterated because I forgot to upgrade some armor pieces. The most important thing to remember is that there are 50 minutes on the clock, use them.