DIY solar panels years back was understood as assembling actual solar panel itself soldering solar cells and assembling it with glass and frame but today when price of solar panels is much more affordable it is more assembling your solar system from available components.
You will need some basic mechanical skills and imagination to mount solar panels somewhere so they do not fly off with the wind. If you know what tale and rafter is then you half way there to install mounting system for your solar panels on your roof (assuming you not afraid of heights). There is plenty different types of solar hooks:
But without getting much in to detail (check YT for “PV mounting system”) you need to slide tile up, fasten hook to the rafter and slide tile back to original position. When PV hooks are in place (that is very often hardest part of installation) not wider then meter apart, and keeping in mind that it is good to have hooks at the ends of planned solar array, all is left is to fasten mounting rail to them. Solar panels are mounted to rail using middle and end solar clamps.
You might have metal sheeting instead of tile on your roof then you will not avoid penetration of it. Most common is sinusoidal shape sheeting or sheeting which looks similar to tile and for that system based on hanger bolt is used. It is special 2 threaded bolt where bottom thread is designed for wood and top is machinery thread for bolt to fasten rail. There is also seal to secure penetration hole so there is no leaking.
There is also metal sheeting where you assemble your panels directly to it without getting deep to the rafter.
Other option is to install solar panels on ground using metal or even wooden frame.
Direct Current cabling is important part of your system and extreme care should be taken when doing it as arcing from DC current is very dangerous in terms of fire. Double isolated cables are used to transfer energy and special waterproof plugs called MC4 for connecting solar panels. If possible, keep your inverter close to solar panels and that way you will avoid long DC cabling.
Inverter heart of the system
Power from your solar panels can be used directly to heat water or produce hydrogen but most of the time we need same type of energy as delivered since years from public grid (thanks to Nicola Tesla it is alternating current). Device which is changing direct current to alternating is called inverter. Inverter has DC terminals where you connect your photovoltaic panels and AC terminals where you connect your devices which are consuming energy. There is 2 types of inverters, those which work with public grid and synchronize to it called grid tie inverters and independent inverters called off grid inverters.