...if you are even remotely interested in pocket watches then you need two things:
(1) The Book.
It's called The Complete Price Guide To Watches by Shugart, Engle & Gilbert. Any Edition will do and the cheaper the better. The book can be bought online for as little as $5 plus shipping. However, while two-thirds of the book is on wristwatches, it's the first third on pocket watches that is of interest to us. Bizarrely, according to Amazon, the next edition of the book will be wristwatches only which is another reason to buy one now.
(2) A pocket watch knife.
While almost any knife will do, I humbly recommend the one I use which is a Bergeon ref. 7403.
Bergeon is black and AF is blue but they are identical knives.
(3) A loupe.
Absolutely essential. 2.5 to 3.5 is a good size to start with for pocket watches and if you haven't got one yet then: