The way I do it is as soon as I write down the Seed, I close the Wallet, then re launch it and use the Restore option. Enter the Seed from the paper I just wrote and go from there.
This isn't even enough: you should check if the seed creates the same address again.
I prefer to test the seed with a different application. So when I setup a hardware wallet, I import the seed into Ian Coleman's software (of course running offline, air-gapped, running a Live Linux DVD from RAM, with the curtains closed on a computer that I'll burn in holy fire afterwards), and see if I can reproduce the same address by different means. It's a lot of work, but being thorough gives peace of mind.
What I normally do whenever I create a new seed is to snap it with another phone
This turns a hot wallet into an even hotter wallet. You're basically doubling the malware risk.