(Sry for long note, but have lots of experience doing this, and therefore built products to help solve these pain points)

I find this is most couples, so take my answer for you with a grain of salt.

But some prerequisites first;

1. Do you know this couple well (of course if youre attending the wedding)? Like close friends or even family?

2. What is your personal gift budget?

These are asked because

a) if you're close with them, you can be their guide with your gift (uncle Jim model)

b) if less than ~ $100, please don't gift UTXO (you know why), if more than $250 then a UTXO is fine imo)

Answering these for yourself above,

I'd say its easiest to just give them a QR Code which is an LNURLw, giving them a Lightning wallet on your own node.

Give them a card with steps to redeem them like

"1. Download Zeus/BlueWallet , 2. Scan QR Code , 3. Use your new gift!"

This is easy but only if you know them well like family and are willing to be their uncle Jim, until they learn how to take custody themselves

If its a significant amount, just hand them an opendime (UTXO) & say keep it in a safe place. Again if they lose it, funds are gone forever.

Personal comments;

I no longer give opendimes as gifts like I used to, people lose them, just don't care, or completely forget about it, burning a perfectly good UTXO (sad I know)

I give (only to people close to me first & foremost) LNURLw's, then when they are serious, I help them get a UTXO or they spend the sats as they see fit. Much easier and much better way to not lose sats (seeing if people are actually serious)