OP,
For mastering bitcoin scripting language you need to check resources like this: https://github.com/bitcoinbook/bitcoinbook/blob/develop/ch07.asciidoc

But for creating actual scripts tailored to your needs (like the hypothetical one @ETFbitcoin suggested) without coding it you have two options:

1)lame option: Ignore the mastering phase and just storyboard your requirements right here, waiting for someone to write down a script for you.

2)Try writing down simple scripts tailored to your need and incrementally add more twists to it

In either case, you will end with something like this:
In this 'simple' script, I send funds to an address which is redeemable with 2 of 3 authorized members of a directing board or something, however, after  60 days if the board doesn't reach required 2 votes, one authorized member can join me to reclaim the funds and after 90 days I can do it by myself.

Now that the script is ready, you need the public keys to put in the placeholders and a map. What map? One that tells you the value of each opcode presented in the script. here you could find one: https://en.bitcoin.it/wiki/Script

After replacing public keys in the script you might decide to calculate its hash. You can use libbitcoin-explorer (bx) for example to this as follows:
The result would be the hash of your script and it can be used as the destination of a simple P2SH transaction but you and other people who wish to access the funds in the future should have access to the original script. reclaiming complex scripts is another story.