How can I make over a queen size bed into a lake house bed?

Please describe your version of a lake house bed? Typically country rustic feel to it. Is that what you are looking for?

Change out your comforter to a light weight quilt. Don't forget to add a sham across one corner of the bed. There is lots of ideas on Pinterest!

Jeannie: maybe these will help

https://thediymommy.com/rustic-traditional-lake-house-master-bedroom-reveal-one-room-challenge/

https://www.danslelakehouse.com/2018/10/peaceful-bedroom-decor-makeover.html

If your going for the cabin feel..... I like the old time toille fabrics, in fact I'm making curtains for a client's RV right now in moose print toille..... https://www.pinterest.com/search/pins/?q=cabin%20toille%20fabrics&rs=typed&term_meta[]=cabin%7Ctyped&term_meta[]=toille%7Ctyped&term_meta[]=fabrics%7Ctyped

We also had 50s kitchy cowboy prints.... https://www.fabric.com/find?SearchText=cowboy+prints

Buffalo checks were big.... https://www.fabric.com/find?SearchText=buffalo+checks

Chinz slipcovers were big on sofas and chairs for easy washing.

https://www.brylanehome.com/b/bedding-and-bath/bedding/quilts-and-coverlets/

Wrap it in jute twine for a rustic look