How do I transcript the DNA strand of 3'-TACCCTTTAGTAGCCACT-5' into mRNA?

First you produce the mRNA complement.
AUGGGAAAUCAUCGGUGA

Then you translate it into a protein sequence by translating the codon triplets using the standard genetic code:
AUG  GGA  AAU  CAU  CGG  UGA
Met    Gly    Asn    His    Arg    STOP

When doing DNA into mRNA, the normal DNA complementary base pair for Adenine, thymine, is replaced by uracil (similar in structure, T has an added methyl group). So this transcription would look like:

5'- A U G G G A A A U C A U C G G U G A - 3'

Now note, luckily AUG is the first reading frame, because its the start codon.  Otherwise you would have to locate the first start codon (the first AUG), and have that as the initial reading frame.  Also note that UGA happens to be the last three base pairs, which happens to be a stop codon (other stop codons are UAA and UAG, but do not appear before the UGA). So the corresponding amino acid sequence is

Met- Gly - Asn - His- Arg- STOP

A list of all the 20 amino acids and their corresponding codons can be found online. Double check the work I did.