the best present is one that you make yourself
这个句子有问题.准确的应该是这样的：
the best present is the one that you make by yourself.
one 是前面 the best present的代词,是特指,且后面用了定语从句强调,必须加 the.
另外,亲手做的,短语是 make (sth) by onself / in person.
make yourself at home 别客气 / 请自便.
希望楼主在审核一下原句.有时候也要自信的质疑书本中和已存在的错句.欢迎追问!