To Clean
する verb
掃除 is cleaning, so the verb version would be to clean.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own. Also, it'll help to know the word 掃除 as well.
「今朝は4時から起きてるよ。」「嘘でしょ？いったい何してるの？」「えっと…家を大掃除してるの。」
"I’ve been awake since four this morning." "No way! What have you been doing?" "Well, just cleaning around the house."