A reasonable person would prefer not to answer your question because disclosing your own setup extremely weakens the security of funds.
If one uses the most common solutions, he cannot weaken the security since the thieves will clearly seek for those if they come for bitcoin.
Of course, this is correct as long as one won't give extra details
It worth mentioning that one of the best solutions to not "weakens the security of funds" is to avoid boasting about owning bitcoins.
I'd say if the DIY security solution is based on reliable non-DIY algorithms, you are doing it right. For example, don't use self-invented encryption methods to hide your seed because you're unlikely to come up with something that is more strong than current encryption algorithms. Moreover, the specification for your algorithm exists only in your memory, whereas standard algorithms can be found on the Internet (unlikely to be forgotten by everyone at once). As for materials to back up your seed words, the choice will depend on many factors, including a location you live in. Maybe you are living under an authoritarian regime and planning to flee your country in the foreseeable future. In that case, engraving seed words on a metal plate wouldn't be a very smart idea since (1) a metal plate is easily recognizable and confiscatable, (2) it is indestructible (but you don't want to leave your seed words behind).
The more non-standard is the solution, the more the need to keep the seed at hand to avoid forgetting about it, hence weaken it.
The more complicated is the solution, especially if it contains steps or passwords only you know, the more the chance those funds will be lost, sooner or later (memory is sooo unreliable and fragile...)
So even if it's based on known and reliable algorithms, I recommend to be used something very simple and known.
And I agree though about metal plate like solutions. I've even written to such a solution that the metal plate looks better as a collectible to be displayed than something to hide with the seed.
