I have been thinking of giving it a try and I'm finally ready to commit. I'm not exactly sure where to start since this will be my first long speedrun (1 hour+). I am wondering if there are any guides or anything similar around, or should I begin to plan my own route to start with? Also, if CornbreadMuffins sees this, could I get a copy of the splits you used and a bit of insight into the run? Thanks for any and all advice :)

If it's your first run that is more than 1 hour, I would really not recommend 100% because of how daunting it is. I would probably recommend a category like all worlds, spongebob rta, or no scrolling sections since they are all more manageable and shorter than 100% (100% is 4 hours and the other categories mentioned are less than 3).

However, if you still want to do 100%, the route is basically all sleepy seeds + snooze z routing, but at the end you have to grind for snooze z's since even if you collect as many as you can throughout the worlds, you still wont have enough to buy everything in the shop. The best level to grind in is SSP. I believe the resources tab provides a guide of where the sleepy seeds are.

Alright, sounds good, might have a look at practicing IL 100% runs to get a grip of what to do before jumping straight into the deep end. Is there any updated guides for NSS runs out there or would I just have to learn it through the all worlds guide? I started thinking about doing a longer run since I've got a hell of a lot more free time on my hands, so I thought learning a long run could be something to do with my time. Thanks for the advice. :)

NSS has the same strats as all worlds, it's just that the autoscrollers are excluded. I think chatter's working on an all worlds tutorial which is a bit more updated than sam's tutorial so you can also use that as a guide whenever it comes out. :)