Clone x gel no humidity dome can I still used with just soil?

A dome is not a requirement but a tool to keep humidity high while the clone develops a root system! Clones are pretty much rootless plants, which means they have no moisture uptake from the medium therefore the moisture in the air supplies it through the leaves. CloneX is just a rooting hormone mixture that increases the rooting speed of your clone, if you keep higher humidity then your clones will root more easily, and slow root growth will happen if not enough moisture is supplied. You can easily DIY a plastic dome with couple of holes in it to keep moisture levels high (a humidifier can also be used) but you can also just dip it in the CloneX, plant it and wait for roots to pop out. It will take more time but that doesn't mean it wont root. I personally rooted clones with house light and minimum moisture, it just took them awhile. *Btw you could also use honey as a replacement for rooting hormones such as CloneX, it is not as efficient but it's a low-cost temporary solution. Hope this helps! Good luck and happy growing :)