Text Contrast
I think something that can be lost or forgotten about a lot when coming up with colorful websites is text contrast as an accessibility feature. Even when not talking about accessibility, sometimes people get it mixed up and make stuff that’s technically viewable but really hard on the eyes to read.
My big thing is that text has to be either significantly / really noticeably lighter or darker than the background it is sitting upon.
While other websites are adventurous with regards to text colors, by and large I use a pretty simple rule of thumb.
BODY TEXT MUST BE BLACK OR WHITE ONLY!
Sure, having text in fun colors can be fun, and technically I do break this little rule with regards to having bolded text, links, and heading text not being black or white. But all the same, the most of the text cannot be a different color than black or white when I’m doing my little webpages.
As mentioned earlier, for custom color pages, I like using coolors to generate a color swatch / theme to work around. The website also shows you when generating the colors whether black or white text contrasts better on it. It can also check whether or not both black / white contrasts well (that is a very small but handy list, the colors that both black and white stand out against). It actually has a lot of cool hidden features not locked behind pro that can make picking out colors really handy.
You do not have to adopt this rule, this is just a rule I use to try to make my website more accessible, in that it keeps things consistent for readers alongside Black and white being great to use for high contrast colors against other colors. Consistent expectations aren’t a bad thing in this regard.
In the hypothetical scenario of doing monochrome / gray scale themes, I will usually try to lean more towards black text on white background than white text on black background. I got away with fudging it on my In Stars and Time Page, by having it white on a darker grey, though for a few other pages I’d like to launch at some point, I’m likely to default to white bg black text (because sure you can do black pages white text, and technically that is accessible, but personal preference for me since I have astigmatisms which can make it hard for me to read white on black backgrounds compared to white on dark but not black backgrounds).
Resources
Never be afraid of using resources. There's lots on the internet that can be helpful for learning and for using. You don't need to be able to do everything right off of the bat.
My credits page is an example of a resource spot, and many folks here on neocities aren't afraid of sharing where they learned how to do things or resources that are free to use.
Do be careful and don't just strip resources from stuff that's not free to use. I know some folks out there are want to do that to get around learning, but learning is always better in the long run.
Be open to learning new things!
Granted this is also just a me thing but given that I learned html / css not from sandbox websites, but from a website that had janky code and a lot of it was just forcing the code to do what you want, I learned some bad habits.
Namely, how to pretty much do CSS Grid / Flexbox through fixed positioning HTML.
Is it possible? Technically yes.
Should you do this? No, not really.
Turns out while I did technically learn the fundamentals there pretty well, we have technology, and can do things better.
You'd be surprised by how much you can learn by doing some simple googling and reading documentation (provided it's not too dense; these days people are making documentation a little bit more approachable). The aformentioned CSS Grid / Flexbox thing was fun to learn vis a vis some online conversations