Depending on the situation, I use different communication methods when talking with people from overseas.
If I want to convey the content accurately, I use email to do so.
ご質問ありがとうございます。
"Depending on the situation,"=「状況によって」
"I use different communication methods"=「違うコミュニケーションの手段を使う」
"when talking with people from overseas."=「海外の人と話すときは。」
"If I want to convey the content accurately,"=「もし正確に内容を伝えたいときは」
"I use email to do so."=「メールを私は使う。」
ご参考に。