How to get rid of moss in the garden before it happens

https://www.thespruce.com/how-to-get-rid-of-moss-in-lawns-2132201

Lime

that's going to be a challenge, since the conditions for moss are damp, shaded, and acidic...

I'd be tempted to pull up the grass instead, and keep the moss.

using lime to 'sweeten' the soil is all I can think of, because any organic material you add to help the soil drain will break down and acidify it all over again.

improve drainage and light --- I love moss --- doesn't need mowing, stays green all year, virtually pest free ( bugs don't live in moss );

As Jean noted you are going to have to try and deal with the damp, shaded and acid. Can you remove any overhanging vegetation to get more sunlight? Perhaps raised beds for some flowers or bushes to reduce the size of the problem In the states I would recommend azaleas or conifers( a ground-hugging juniper?) Perhaps a gravel walkway. In a more extreme move perhaps a French drain to dry the soil.

You don't have to mow moss...just sayin...

Thanks for all your answers. I will spread some lime. Does this come in powder forms?