Hi saood, I live in Dubai and we have similar climate. I am no expert but I tried sfg last year and it was good. I didn't follow exactly though. First of all I couldn't find vermiculite so I skipped it. I didn't use wood but used interlock tiles and cinder blocks instead. I didn't just put the mix in the beds but I also mixed it with the sand below (things were getting expensive already, and I also felt 6 in is not enough so by mixing I "improved the soil below for veggies with longer roots). I added manures, chicken and cow, and fish pellets. This was enough for the season and tomatoes did amazing, best of all after radishes. If you remember the book says to add compost every season, so just add every season, or mid season too. Remember we have sand and nutrients leach away fast, that's why we are adding compost and vermiculite, they help with nutrient retention, but in our climate we may need to add more frequently. Wish you a good garden, don't forget to share photos. Here's a pic of tomatoes from last year.

And here's a pic of beets, they also did well. Radishes were amazing too, but the round ones didn't grow till it was cold, but the "18 days" long variety did amazingly well, as well as white radish, which we call "ruwaid" (I don't know if you also use the same name), we only eat the leaves of it not the roots.