I've popped the dough in the fridge, ready to cook tomorrow evening, fresh for a Birthday BBQ on Thursday.
...Beanie's Guide to Biscuits and Cookies
From my experience cookies and biscuits tend to be a lot easier to make when comparing to cakes. You can be lazy with the quantities as the rise of the cake etc. doesn't matter. The trick is to keep watching them til they turn your desired level of crunchiness - use the golden edges as a colour.
Don't panic if you're cookies seem to be floppy and fall apart straight out the oven - you must leave them on the tray to cool a bit before transferring them across to a cooling tray. They stiffen up (stop it you dirty bunch) as they cool, so I choose to opt for overly chewy than over-baked and crispy.
With cookies (as opposed to biscuits) the timing matters even less as a few minutes here and there just varies how soft they are.
I always up the number of chocolate chips recommended in recipes, as I like plenty of 'bits' in my cookies. Provided they stay together you shouldn't have an issue adding more chocolate pieces or nuts, or sprinkles or fruit or...
Another shortcut I always take is switching 'proper/posh' chocolate chips and just bashing up bars of chocolate instead. This way is much cheaper, plus you get bigger chunks of chocolate-yness. The 100g bars from Lidl/Aldi are perfect as they are thinner and easier to bash up than Diary Milk. Or if your feeling posh the Lindt chocolate bars are perfect bashing material.