I am not a military professional but as a mean to defend yourself against the military might of Israel you should try to destroy some of their tanks. When some of these tanks are put on fire and turned into rubble you can use them as strong shields and barricades.

Even better if you are able to capture some of their tanks. And with surprise insert a heavy bombardment against their installations and other tanks.

You should try to get anti-tank weapons and weapons that are able to penetrate the armor of those vehicles.

Homemade weapons might also work, if correctly used. The danger ofcourse is that you have to be physically very close to a tank.

What about conventional unconventionality.

If you have the right equipment and people who can use them you could jam at least parts of their communications.

The Greeks used guerilla tactics on their islands against the nazis occupying them during second world war. One legendary move was to thrust(throw) in a wasp`s nest in a windmill where german soldiers were stationed. Those hornets got really angry and you can imagine what happened with those german soldiers. They were forced to get out from the compound.

Studying Leonardo da Vincis military mechanisms is not probably the best time to do that now, but if you have(palestinians) as I presume a shortage of bullets, you could put up strict lines of defence.
One window - one armed post.
You could place tubes in several different directions. And one guy in the tube takes care of his line of fire, the other tube takes care of his line of fire, the third tube takes care of his line of fire etc. When there is a shortage of ammunition you could try this method.

What about petroleum beds? You could put on fire a line of rubble. Barricades on fire. You might stay safer for a while behind a smokescreen.

Everything mentioned above are however not even a substitute against an army that is equipped with modern jetfighters, tanks and artillery.

I am not adressing suicidebombings, although I can comprehend the desperation on the Palestinian side. It is horrible to see young children die because of those suicidebombs. You need your people on the front. Those women and youth who are ready to use fireweapons could quickly
be turned into guerilla fighters. Not suicidebombers.

You could make 10 000 molotov cocktails. As many as you can.

Where have those Qassam-missiles disappeared?

I feel strongly to support the side that is weaker and has practically no military resources. However I do not support the brutal violence used against the civilian population on both sides.

Israel is making this conflict into a global nightmare by shooting and seriously wounding peaceful solidarity envoys.
More solidarity groups are expected to the conflictzone.

Eventually the only way will be the way of peace. The way of peace along with justice.

Solidarity