I used crochet for my razor cami (pattern available online by Katie from allmystars). I didn't want a strappy top I couldn't wear to work and knitting small cap sleeves seemed too difficult. Crochet is so much easier! So I just took a crochet pattern I had and added this to the top part and a random pattern for the bottom (the knit ribbing at the bottom didn't look good so I had to cut it off).
This pattern can be added to any knit tube so I've added the pattern (chart!!!) for you
Crochet cami picture
Corchet cami pattern