Storing your seed phrase is not an issue, but how safe you keep it matters because that is the only thing that can guarantee it to be well secured. Many people save their seed phrase in many ways that best suit them.
Saving your seed phrase in ways that best suits you is not the best idea because many have saved their seed phrase in their emails, sheets, notebooks and other resources they have access to always and others can also have access to when compromised and it didn’t go well for them. So desist from using any method that best suits you which you find very easy to access back. Making it so simple may cost you more to lose your funds in the long run. Make it hard to grasp and taken over by anyone except yourself.
As stated by some members here, you can adopt any of them that you feel is comfortable for you to go with, but the easiest is just to write down your keys and store them in any safe place where only you have access to, so that nobody gets them from there so easily. This is what I do, and I have my keys intact till today. Only I have access to my keys, and it is safe where I keep them.
Having your seed phrase written down and safe in just one place is not the best approach to have a safe wallet. I don’t think no matter how securely you can keep your phrase, there can be compromise especially if you are not living alone but staying with your family. Wallet security is the first step of having a safe investment in Bitcoin. If you’ve made a mistake in this, you’re just as good as someone that has never invested before, so make it a necessity to protect it at all cost.