Hey, just a tip for Inkarnate, use the less ornate fonts for locations other than regional names. It increases readability and you can make them smaller.
As for getting started, everyone else has given great advice. Just a warning from a fellow Photoshop user, Photoshop is an amazing application but it comes with a lot less free stuff than gimp. Also many of the tutorials here are gimp specific. So, have gimp downloaded and be prepared to switch back and forth between the two programs if you're set on using Photoshop. I'm not sure if I regret not just using gimp from the beginning, but in the end it's better to use what you're familiar with.
For example, if you're looking to follow Arsheesh's tutorials or ones like them, you'll need to use gimps bump map for mountains. Photoshop has excellent 3D capabilities and is more than capable of creating a simple bump map -- but there's the problem. The 3D tools are really complicated and if you're not really familiar with them you'll come out with a mess. The 3D suite is like an entirely different program.
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