German genders feel random, but some word endings and groups are very reliable:
    die – words ending in -ung, -heit, -keit, -schaft, -ion: die Zeitung, die Freiheit, die Möglichkeit, die Freundschaft, die Information das – diminutives ending in -chen and -lein: das Mädchen, das Brötchen (even when the person is female!) der – days, months and seasons: der Montag, der Januar, der Sommer
The best general tip: always learn a noun together with its article, never just "Tisch" but "der Tisch". Quick quiz: what's the gender of Bedeutung, Kätzchen and Winter? Post your guesses, and share any trick that helps you remember genders.