The direct answer to your question is here:
https://documentation.concrete5.org/developers/working-with-blocks/c... (and subsequent pages).

However, there's a lot more to it than HTML/CSS/js. You need a fair bit of php to make it play nicely with c5. It could be cost-effective to see if there's an add-on in the marketplace that does what you want, or near enough such that it could be easily modified.

Also worth having a look at one of the block building addons, such as block designer. You can learn a fair bit by seeing how they build the skeleton of a block for you, even if you then go on to build blocks by hand.

Hi both,

Thanks for providing the above.

I need to look at developing my own blocks then?

Maybe we have jumped in too deep and you are asking about the basics of add/edit, rather than custom blocks.

The core comes with a slider block. There are many addon slider and slideshow blocks in the marketplace, paid and free.

You add a block by clicking on the + icon to the left of the top bar. The block add panel slides out. Find your block type on it and drag it onto the page. There is plenty more about this in the documentation and also on many videos.

You would prepare a page with a slideshow block on it, then enable your customer to edit the slideshow block on that page using permissions. It depends how tightly you want to tie the permission down.

Hi John,

I understand the concept of adding blocks to a page etc. I am developing a custom theme for a customer (currently integrating CMS to the HTML) and I know that there are slideshow addons already but as I plan to use concrete5 for future web development projects; I want to know that I have the ability to create my own content types i.e. slideshows, custom galleries and so on for reassurance purposes as I like to offer a bespoke service.

Then yes, you can do that.

But only do it when it's not cost-effective to adapt what's already out there.