It's more important to avoid having things that don't go with your room than it is to have things that suit your room.
ーIf you want your room to look harmonious, it's more important to avoid having things that don't go with your room than it is to have things that suit your room.
「部屋に調和を求めるなら、部屋に合うものを置くより、合わないものを置かない方が大切だ」
to look harmonious で「調和して・調和がとれて見える」
to avoid で「避ける」
to go with ... で「…と合う・調和する」
to suit で「合う・適する」
ご参考まで！
カナダ 
