Now I know this is self-evident. But, since I have had an "OMG, I'm ~such~ a moron!!" experience today, I thought I would offer a bit of advice to keep others from making the same mistake.
Many moons ago I purchased new clubs... the works, R9 Driver, Tour Starter set, etc. I noticed right away longer drives and better, more accurate approach shots. It was really good. But I still couldn't putt worth a damn... Oh well, I'll get better with practice, right?
Yesterday I happened to notice that I had not yet equipped my new putter and that I was still using the Starter putter.
/facepalm
So, I finally equipped it... and had some very good results.
Will it make me good enough to become a Master? Probably not, because I still suck at this game... but still, every little bit helps.
So, when you buy clubs, equip them.