Is practicing speaking the only way to improve my English?
Practice speaking is great, but you should know it's also of extreme importance to read English books.
Reading introduces you to a lot of useful expression, for example.
Why don't we buy Dad a red jacket for his birthday?
I think red will suit him.
Hmm.., a red jacket for 68-year-old guy? That's a fun idea, but he might be shocked.
Let's play it safe and buy him the fountain pen that he's been keen to get.