SIPP Question as self employed

Hi guys, I have a SIPP question. I know there's quite a lot of these, but I'm seeing different answers to people's threads vs articles I've read.

I'm self employed, the contributions I make to my SIPP each year, for example, if I made 40k that year and invested 10k into my SIPP, do I just put my income on my self assessment as 30k? Then the 20% bonus on top of that 10k= 12k in the SIPP for that year?

Thanks